TVA
v>EPA
Tennessee Valley
Authority
Division of Energy Demonstrations
and Technology
Chattanooga, Tennessee 37401
EOT 109
United States
Environmental Protection
Agency
Industrial Environmental Research
Laboratory
Research Triangle Park NC 27711
EPA-600/7-80-100
May 1980
          Processing Sludge:
          Sludge Characterization
          Studies

          Interagency
          Energy/Environment
          R&D Program Report

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                 RESEARCH REPORTING SERIES


Research reports of the Office of Research and Development, U.S. Environmental
Protection Agency, have been grouped into nine series. These nine broad cate-
gories were established to facilitate further development qnd ap'piication of en-
vironmental technology. Elimination  of traditional  grouping  was consciously
planned to foster technology transfer and a maximum interface in related fields.
The nine series are:

    1. Environmental Health Effects Research

    2. Environmental Protection Technology

    3. Ecological Research

    4. Environmental Monitoring

    5. Socioeconomic Environmental Studies

    6. Scientific and Technical Assessment Reports (STAR)

    7. imeragency Energy-Environment Research and Development

    8. "Special" Reports

    9. Miscellaneous Reports

This report has been assigned to the  INTERAGENCY ENERGY-ENVIRONMENT
RESEARCH AND  DEVELOPMENT series. Reports in this series result from the
effort funded under the 17-agency Federal Energy/Environment Research and
Development Program. These studies relate to EPA's mission to protect the public
health and welfare from adverse effects of pollutants associated with energy sys-
tems. The goal of the Program is to  assure the rapid development of domestic
energy supplies in an environmentally-compatible manner by providing the nec-
essary environmental data and control technology. Investigations include analy-
ses of the transport  of energy-related pollutants and their health and ecological
effects;  assessments of, and development of,  control technologies  for energy
systems; and integrated assessments of a wide range of energy-related environ-
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                        EPA REVIEW NOTICE
This report has been reviewed by the participating Federal Agencies, and approved
for publication. Approval does not signify that the contents necessarily reflect
the views and policies of the Government, nor does mention of trade names or
commercial products constitute endorsement or recommendation for use.

This document is available to the public through the National Technical Informa-
tion Service, Springfield, Virginia 22161.

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                                 EPA-600/7-80-100

                                            May 1980
Processing  Sludge:  Sludge
  Characterization  Studies
                     by

            J.L. Crowe (TVA-Chattanooga)
          and S.K. Seale (TVA-Muscle Shoals)

             Tennessee Valley Authority
     Division of Energy Demonstrations and Technology
            Chattanooga, Tennessee 47401
        EPA Interagency Agreement No: D5-0721
            Program Element No. EHE624A
           EPA Project Officer: Julian W. Jones

       Industrial Environmental Research Laboratory
     Office of Environmental Engineering and Technology
           Research Triangle Park, NC 27711
                  Prepared for

       U.S. ENVIRONMENTAL PROTECTION AGENCY
          Office of Research and Development
               Washington, DC 20460

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                              DISCLAIMER
     This report was prepared by the Tennessee Valley Authority and has
been reviewed by the Office of Energy,  Minerals,  and Industry,  U.S.
Environmental Protection Agency, and approved for publication.   Approval
does not signify that the contents necessarily reflect the views and poli-
cies of the Tennessee Valley Authority, nor does  mention of trade names
or commercial products constitute endorsement or  recommendation for use.

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                               ABSTRACT
     This report summarizes work completed during the period March 13,
1975, to June 30, 1977.  The main emphasis of this work was to determine
the range of variability of the solids from scrubbers operated at the
Shawnee test facility and to attempt to correlate this variability with
plant operating conditions.  Slurry and solids characterization studies
were conducted on 167 samples obtained from the turbulent contact absorber
(TCA) and venturi-spray tower scrubbing systems.

     Systems operating with limestone as the absorbent precipitate
CaSOs*0.5H20 primarily as single plates and relatively flat rosette forms,
while spheroidal aggregates of many small plate crystals are formed when
lime is used.  The form of sulfite morphology observed is shown to be
independent of scrubber configuration.  Clear evidence is seen of the
relationship between the crystal size (in limestone systems) and system
Ca:S ratio (stoichiometry), although no such relationship is observed in
lime systems.  The difference in sulfite crystal morphology observed
between lime and limestone systems is attributed to precipitation and
crystal growth rates.  When forced oxidation is used with either absorbent,
the reaction product is seen to consist of very large, blocky CaS04*2H20
crystals; no CaSOg'0.5^0 forms are seen.

     A simple and rapid method for the determination of gypsum in scrubber
solids (over the range 0.1 to 10.0 wt. percent) was developed.  The peak
area resulting from gypsum dehydration (using differential scanning colori-
metry) is directly and linearly proportional to the concentration of gypsum
in a sample.  This peak is not obscured or interfered with by other compon-
ents in the sample matrices and thus provides a clear distinction between
gypsum SQ~4 and substituted 804 .

     Statistical analysis of the venturi-spray tower data resulted in
regression models which characterize the percent settled solids and per-
cent bulk density as a nonlinear function of calcium sulfite solids and
the percent solids recirculated.   Behavior of the solids produced by both
lime and limestone systems are summarized for low and high levels of
oxidation.

     High levels of settled solids (50 percent or more) for both the lime
and limestone product sludges are associated with high oxidation, high
percentage solids recirculated, high fly ash content, and low sulfite
solids.  Low percentages of settled solids (35 percent or less) for both
systems occur with low levels of solids recirculated, average oxidation,
low fly ash content, and high levels of carbonate.

     High levels of settled bulk density, for lime and limestone product
sludges, of 1.4 g/cc or more are characterized by high oxidation, high
levels of solids recirculated, high fly ash content, and low sulfite solids.
As a contrast, low fly ash content, high percentages of sulfite and car-
bonate, and solids recirculated plus low oxidation are noted for settled
bulk densities of 1.2 g/cc or less.
                                   111

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                               CONTENTS
                                                                  age
Disclaimer	    ii
Abstract	iii
Figures  	     v
Tables	vii
Acknowledgements 	  viii
Section

   1      Introduction 	     1
   2      Conclusions and  Recommendations 	     2
   3      Instrumental Techniques of Characterization  	     4
   4      Solids Morphology  	     5
               Sulfite Morphology  	     5
               Morphology of Accessory Components  	     8
               Morphology of of Solids Formed Under
                 Forced Oxidation  	     8
   5      Slurry Settling Behavior 	    10
   6      Solids Surface Area Measurements 	    14
   7      Thermal Analysis of Scrubber Solids  	    15
   8      Statistical Analysis 	    17
               Mean Values	    17
               Percent Settled Solids  	    17
               Settled Bulk Density	    18
               Relationships Found in the Data Using
                 Regression Analysis 	    19
               Regression Models - Statistical
                 Considerations  	    20
   9      References	    22
                                   IV

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                                FIGURES


Number                                                           Page

   1      Photomicrographs illustrating various forms in which
          CaS03-0.5H20 is found in scrubber sludge 	   22

   2      Photomicrographs of CaSOs-O.SHgO aggregates formed
          when lime is used as the absorbent	24

   3      Photomicrographs of CaSOs'O.SH^O plates formed when
          limestone is used as the absorbent	26

   4      Photomicrographs of CaSC>3'0.5H20 aggregates formed
          when lime is used as the absorbent	28

   5      Photomicrographs of CaS03'0.5H20 plates formed when
          limestone is used as the absorbent	30

   6      Photomicrographs of CaS03'0.5H20 aggregates formed
          when using lime as the absorbent	32

   7      Photomicrographs illustrating the relationship
          between CaSOs'O.Sl^O plate size and scrubber system
          Ca:S stoichiometry with limestone as the absorbent . .   34

   8      Photomicrographs of "Mixed Crystals" forms 	   36

   9      High-magnification photomicrographs of sulfite-gypsum
          "Mixed Crystals" forms 	   38

  10      Photomicrographs of sludge solids components with
          and without forced oxidation on the same system
          (venturi/spray tower)  	   40

  11      Slurry settling rate curves  	   43

  12      Photomicrographs of solids producing settling
          behavior shown in Figures 11B	   44

  13      Settling rate of lime and limestone scrubber
          slurries	46

  14      Settled bulk density for lime and limestone scrubber
          slurries	47

  15      Distribution of settled solids content values for
          solids produced under lime, limestone, and fly ash-
          free operation	48

  16      Distribution of surface area values for solids
          produced under lime, limestone, and fly ash-
          free operation	49

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                                FIGURES
                              (Continued)
Number

  17      Thermograms for lime and limestone-product sludge.  .  .   50

  18      Final settled solids content of limestone scrubber
          slurries as a function of sulfite content	51

  19      Final settled solids content of limestone scrubber
          slurries as a function of recirculated solids	52

  20      Perdicted and observed final settled solids content
          for limestone scrubber slurries	53

  21      Settled bulk density of limestone scrubber slurries
          as a function of sulfite content	54

  22      Settled bulk density of limestone slurries as a
          function of recirculated solids content	55

  23      Predicted and observed settled bulk density for
          limestone scrubber slurries	56

  24      Final settled solids content of lime scrubber slurries
          as a function of sulfite content	57

  25      Final settled solids content of lime scrubber slurries
          as a function of recirculated solids content 	   58

  26      Predicted and observed final settled solids content
          for lime scrubber slurries	59

  27      Settled bulk density of lime scrubber slurries as a
          function of sulfite content	60

  28      Settled bulk density of lime slurries as  a function
          of recirculated solids content 	   61

  29      Predicted and observed settled bulk density for lime
          scrubber slurries	62
                                   VI

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                                TABLES


Number                                                           Page

   1      TCA Slurry Analyses	63

   2      Venturi/Spray Tower Analyses 	   70

   3      Settling Rate Determinations 	   77

   4      Temperature of Dehydration of CaS03-0.5H20
            In Dried Scrubber Solids 	   78

   5      Analytical Results for Gypsum Determination by DSC .  .   79

   6      Analytical Results for the Venturi/Spray Tower
            Sludge Data	79

   7      Mean Values for High Settled Solids	80

   8      Mean Values for Low Settled Solids	80

   9      Mean Values for High Settled Bulk Density	81

  10      Mean Values for Low Settled Bulk Density	81

  11      Predicted Response for Changes in Variables--
            Limestone System	81

  12      Coefficients and Standard Errors from
            Regression Analysis  	   82

  13      Evaluation Statistics from Regression Analysis ....   82
                                   VI1

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                            ACKNOWLEDGEMENTS
     This study was initiated by TVA as part of the project entitled
"Processing Sludges from Lime/Limestone Wet Scrubbing Processes for
Disposal or Recycle and Studying Disposal of Fluidized Bed Combustion
Waste Products," and is supported under Federal Interagency Agreement
Numbers EPA-IAG-D7-0721 and TV-41967A between TVA and EPA for energy-
related environmental research.  Thanks are extended to EPA project
officers, Dr. Theodore G.  Brna, Julian W. Jones, Michael C. Osborne, and
John E. Williams.   Appreciation is also extended to Chris Gottschalk,
R. A. Hiltunen, G.  H. McClellan, and S. K. Seale.
                                   VI11

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                                Section 1

                              INTRODUCTION
     Sludges produced by flue gas desulfurization processes have been
extensively characterized both chemically and physically in the past, but
usually this type of study has been only of short duration, not defining
the total range of variability of the solids or relating any of the char-
acteristics to scrubber operation.   With the increasing use of sludge
treatment processes, this lack of research in solid characterization pre-
sents problems when designing such systems for economy and efficiency of
operation, since the chemical and physical makeup of the sludges directly
impacts the handling and disposal requirements.

     One of the purposes of this study has been to provide a long-term,
comprehensive chemical and physical characterization of lime and lime-
stone scrubbing sludges produced at the Shawnee Test Facility.  Where
possible, a collateral goal has been to relate sludge properties such as
settling rate and final (settled) bulk density and solids content to pro-
cess operating conditions such as initial sludge solids content, hold
tank residence time, system Ca:S stoichiometry, presence of fly ash, sludge
pH or temperature, liquor chemistry, etc.  This study also has included
investigations on the conditions of optimum crystal growth because of the
significance of this factor on pond site dewatering, filtration rates, and
liquid entrainment in the solids.

     This report presents all data collected on samples taken from the
turbulent contact absorber (TCA) and venturi/spray tower systems over the
period of study March 13, 1975, to June 30, 1977.

     This investigation has used comparative optical and electronic micros-
copy, x-ray diffraction, infrared spectrophotometry, and thermal analysis
to provide a comprehensive study of the range of variability observed in
sludge phases from the Shawnee scrubbers.  Settling rates and determina-
tions of the final solids content and bulk densities provide data on the
physical properties of sludges.

     Statistical analysis of the venturi/spray tower data resulted in
regression models which characterize the percent settled solids and per-
cent bulk density as a nonlinear function of calcium sulfite solids and
the percent solids recirculated.  Behavior of the solids produced by both
lime and limestone systems are summarized for low and high levels of
oxidation.

     A simple and rapid method for the quantitative determination of gypsum
in scrubber solids (over the range 0.1 to 10.Q wt. percent) was developed.
This method differentiates between gypsum S04  and substituted S04  .

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                                Section 2

                     CONCLUSIONS AND RECOMMENDATIONS
     Solids produced by the TCA and venturi/spray tower at the Shawnee
Test Facility from March 13, 1975, to June 30, 1977, have been character-
ized chemically and physically.  It has been shown that the primary sludge
component affecting handling and disposal is CaSOa'O.SHgO and that the
form in which this compound is precipitated is an important factor.  Sys-
tems operating with limestone as the absorbent precipitate the CaSOa'O.SH^
primarily as single plates and relatively flat rosett forms, while spheroi
dal aggregates of many small plate crystals are formed when lime is used.
The form of sulfite morphology observed is shown to be independent of
scrubber configuration.  In limestone systems, SEM photomicrographs docu-
ment an inverse relationship between the crystal si2e and system Ca:S
stoichiometry.  No such relationship is observed in lime systems.  The
difference in sulfite crystal morphology observed between lime and lime-
stone systems is attributed to precipitation and crystal growth rates.
When forced oxidation is used with either absorbent, the reaction product
is seen to consist of very large, blocky CaS04*2H20 crystals; no
             forms are seen.
     Sludges produced by both lime and limestone systems are shown to
display zone settling characteristics in the region above an artificial
lower limit of 10 to 12 percent solids; here, settling rates are seen
primarily to be a function of initial sludge solids content, although
solids morphology effects are seen.  At initial sludge solids contents of
10 percent or less, it is seen that clarification settling applies and
that lime slurries settle faster.  When forced oxidation is used with the
precipitation of large gypsum crystals, settling rates are shown to be
five to ten times faster than normal lime- or limestone-produced slurries
in the same range of solids content.  Gypsum slurries are shown to settle
to a much higher final solids content than either lime- or limestone-
derived slurries.  In lime and limestone systems, there are indications
that the presence of fly ash causes an increase in final (settled) solids
content.  While in this study lime and limestone slurries are shown to
retain approximately the same final solids content after static settling
in a closed cylinder, other evidence is provided that shows lime slurries
dewater with more difficulty because of the generally higher surface area
of their solids components .

     Thermal analysis of the dried slurry solids shows that the thermal
desolvation of the CaSOs'O.SI^O component is complex, lending support to
the suggestion th,at this component may be substituted to varying degrees
with 804" or C0^~ •  The range of variability observed in measurements of
this compound's crystallographic properties also supports this premise,
although attempts to show correlations between the temperature of desol-
vation and crystallographic parameters were unsuccessful.

     A simple and rapid method for the quantitative determination of gyp-
sum in scrubber solids was developed.  Thermal analysis of dried scrubber
solids was employed using differential scanning colorimetry.  It was shown
that the peak area resulting from gypsum dehydration is directly and

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linearly proportional to the gypsum concentration in the scrubber solids.
This peak is not obscured or interfered with by other components  in the
solids matrices_and thus provides a distinction between gypsum 864  and
substituted S04 .   Over the range if 0.3 to 10 percent gypsum, determina-
tion may be made with a precision of better than 5 percent and an accuracy
of better than 5 percent.

     Through statistical analysis of sludge data, it was shown that high
levels of settled solids (50 percent or more) for both the lime and lime-
stone product sludges are associated with high oxidation,  high percentage
solids recirculated, high fly ash content, and low sulfite solids.  Low
percentages of settled solids (35 percent or less) for both systems occur
with low levels of solids recirculated, average oxidation, low fly ash
content, and high levels of carbonate.

     High levels of settled bulk density, for lime and limestone  product
sludges, of 1.4 g/cc or more are characterized by high oxidation, high
levels of solids recirculated, high fly ash content, and low sulfite solids.
As a contrast, low fly ash content, high percentages of sulfite carbonate,
and solids recirculated, plus low oxidation are noted for settled bulk
densities of 1.2 g/cc or less.

     It should be noted that the main objective of the Shawnee Test
Facility is to evaluate various scrubber concepts and that the sludge
characterization study was a side effect to this scrubber evaluation.
As a result of this, no specific tests were conducted on the scrubber
to control the characteristics of the sludge produced.  Since the sludge
characterization study has shown specific correlations between scrub-
ber operation and sludge characteristics the next step should be to
verify and demonstrate these correlations through actual control of
scrubber operation.  Thus, a study should be made where the operation
of the scrubber is dedicated to sludge production and characterization
evaluations.  This type of study could best be accomplished at a scale
smaller than Shawnee for economical purposes.

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                                Section 3

               INSTRUMENTAL TECHNIQUES OF CHARACTERIZATION
     During the period March 13, 1975, to June 30, 1977, slurry and solids
characterization studies have been conducted on 167 samples obtained from
the TCA and Venturi/spray tower scrubbing systems located at the Shawnee
Test Facility.  A number of instrumental techniques have been employed in
this characterization.  Scanning electron microscopy (using a Cambridge
S-A SEM) and optical microscopy provided both qualitative and quantitative
information concerning bulk solids composition, as well as the specific
morphological form in which various individual components occur.  Infra-
red spectrophotometry (using a Perkin-Elmer 521 grating instrument) and
x-ray powder diffraction measurements (using Phillips-Norelco x-ray
generators and goniometers) have been used for semiquantitative analyses
of the dried solids and to determine crystallographic unit-cell parameters
of CaS03*0.5H20.  The specific surface area of the dried solids was deter-
mined as an indication of solids component morphology.   Since a portion
of this study involves investigation of the degree to which the calcium
sulfate hemihydrate component may have been substituted by sulfate or car-
bonate species, several techniques have been used which would reflect any
changes in crystal structure caused by this substitution.  Optical micros-
copy was used to provide the index of refraction of this component, while
its specific crystallographic unit-cell parameters, as  determined by x-ray
diffraction, are very sensitive to compositional changes.  In addition,
differential scanning calorimetry (DSC) using a Perkin-Elmer DSC-2 was
evaluated as an indicator of the ease with which the sulfite component
underwent dehydration.  It was felt that the temperature of dehydration
should, in general, vary inversely with the degree of substitution of
sulfate for sulfite.

     Slurries obtained from the scrubbing systems were  characterized by
static settling tests.  Values for the settled bulk densities and settled
percent solids also were determined.

     The results of the chemical and physical examination of the slurries
and solids are presented in Tables 1 and 2.   A discussion of specific
areas of investigation follows.

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                                Section 4

                            SOLIDS MORPHOLOGY
     Solids samples obtained from the TCA and venturi/spray tower,  when
operated under nonoxidizing conditions,  generally contain calcium sulfite
hemihydrate and fly ash as the major species.  Small quantities of  gypsum,
unreacted absorbent, and quartz are also present.


Sulfite Morphology

     The calcium sulfite hemihydrate species is generally the major com-
ponent (50 to 70 percent by weight) of the solids.  A study of its  morpho-
logy and occurrence is important since these factors bear heavily on
handling considerations such as sludge filtration, clarification, and
disposal technique.  It should be noted throughout this report that the
crystalline species referred to as calcium sulfite hemihydrate may be more
appropriately described as Ca(S03) (S04) 'zH20 or (CaS03) (CaS04) "zR2Q
where x is much greater (in the range of^10 times greater* than y and z
approaches 0.5.

     The specific physical form in which the sulfite species appears is
directly related to the type of absorbent used (lime or limestone)  and
is independent of the scrubber configuration (TCA or venturi/spray tower).
The calcium sulfite hemihydrate component of the solids samples received
during this study occurs in several forms (see Figure 1 for examples).
When limestone is used as the absorbent, the sulfite crystallizes pre-
dominantly as well-formed single plates with a length-width-thickness
average ratio of 25:20:1 (Figures 1A and IB).  While within a given sample,
the crystal size distribution will range over an order of magnitude, the
average size may differ only by a factor of two to three from one sample
to another within the same run.  The sulfite crystals in Figures 1A and IB
show the general maximum and minimum sizes observed in limestone runs dur-
ing this study.  While the single plates described above are the major
form observed, aggregated forms of the sulfite crystals also are seen.  An
example of a form appropriately described as a flat or two-dimensional
"rosette" in which many small plates grow outward in all directions,
particularly at low angles, around an axis perpendicular to the plane of
growth is shown in Figure ID.  This form is not uncommon; most samples
examined from limestone-scrubbing operations will contain some incidence
of this rosette form.  A few samples have shown this form as the predomi-
nant sulfite occurrence.  A more open form of aggregate resulting from the
use of limestone is shown in Figure 1C.  These forms consist of  interpene-
trating plates forming relatively open structures of varying size and
shape; their occurrence in small amounts is  a common feature.

     The characteristic form of the sulfite precipitated from  scrubbing
liquors where lime  is used as  the absorbent  is shown in Figures  IE and  IF.
These generally spherical aggregates do not  show  a wide variation  (usually
less than an order  of magnitude) in size distribution within a given  sam-
ple, although incompletely developed forms and fragments are often  seen.
Examination of these spherical aggregates with transmission  electron

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microscopy was undertaken to determine whether or not the aggregates pos-
sessed a central core of nonsulfite material (i.e., fly ash) which may
have served as an initial nucleation site.  Results obtained with this
method were inconclusive due to particle decomposition and fragmentation
by beam heating effects.  It may be noted, however, that spherical aggre-
gate formation is commonly seen in lime scrubbing operation under fly ash-
free conditions.  Therefore, to clearly demonstrate that the sulfite habit
is scrubber-independent and absorbent-dependent, the samples obtained from
the venturi/spray tower scrubber over the period March 13, 1975, to June 27,
1976, may be subdivided into five separate groups:

     A.   3-13-75 to  10-5-75, lime scrubbing, Figure 2
     B.   10-12-75 to 1-31-76, limestone  scrubbing, Figure 3
     C.   2-15-76 to 3-2-76, lime scrubbing, Figure 4
     D.   3-6-76 to 4-21-76, limestone scrubbing, Figure 5
     E.   5-1-76 to 6-27-76, lime scrubbing, Figure 6

During this period the use of limestone as the absorbent was alternated
with that of lime as  seen above.  The results repeatedly show the spheri-
cal sulfite aggregate occurrence  (Figures 2, 4, and 6) when lime is used.
When limestone is used, however,  flat plates are seen to predominate
(Figures 3 and 5).  A probable cause for  this clearly-established absorbent-
morphology relationship appears to lie in the difference in precipitation
rates  for the two forms; i.e., the spherical aggregates formed under lime
scrubbing operation are a result  of much  faster sulfite precipitation than
the larger single plates formed with limestone operation.  Several factors
argue  in favor of this explanation.  One  of the most significant features
is the obviously greater complexity of the sulfite forms precipitated when
lime is used.  Complex crystalling forms; rather than larger single crystals,
are commonly observed when precipitation  rates are high.  Also, the optical
and x-ray crystallographic properties  (index of refraction, lengths of
unit-cell axes) show  greater variation in the lime-derived sulfite.  These
properties are very sensitive to  variations in the crystal structure of
the compound caused either by inclusion of ions "alien" to the parent
lattice  (Na  , K  , S04~, S03~, etc.) or by large scale lattice defects of
a nonstoichiometric nature.  Both foreign ion inclusions and lattice
defects  are  commonly  a  result of  rapid precipitation.  Another  contribu-
ting piece of evidence  is the difference  in particle size distributions
observed between  limestone-  and  lime-derived sulfite forms.  The much
wider  distribution  of crystal sizes seen  in samples consisting  of  single
plates indicates  continual  crystal growth.  The narrower distribution of
sizes  seen among  the  spherical aggregates infers  a more rapid initial
growth within this  same  sampling  interval with  growth having been  termi-
nated  at  the maximum  size permissible  in  the scrubbing  system.

      Special attention may  be  given to Figure 6F  in which  the aggregates
are  seen to  consist of much smaller, more densely inter-penetrating plates
 than observed  in  other samples  in this study.   Although the  exact  cause
 of this differentiation is  unknown,  it should be  noted  that  the level of
 the  chloride ion  in the scrubbing liquor  is much  higher for  the time  at
which this  sample was taken (2.13 percent by weight)  than for any  other
 sample studied  in this system.

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       In lime systems, no definite relationship was seen between aggregate
  size or complexity and either chemical composition or physical/chemical
  operating conditions.  In attempts to determine such a relationship,
  factors such as stoichiometric ratio, pH, slurry temperaturea hold tank
  residence time, make/pass,  L/G,  weight percent of Mg   or Cl  in the
  liquor,  and the presence or absence of fly ash were studied.

       When limestone is used as the absorbent,  the average size of the
  plate crystals  formed in this  environment appears to be inversely related
  to  system stoichiometry,  as shown in Figures  7A through 7F.   The  micro-
  graphs  show a steadily decreasing average crystallite size with increasing
  Ca:S  ratio.  While  no precise  mathematical relationship has been  derived,
  this  observation argues  in  favor of stoichiometries  approaching 1,0 in
  order to  promote faster  slurry filtration and  clarification.   Unfortunately,
  S02 removal  efficiency suffers at such  low stoichiometries.

      Attempts also have been made to  relate crystal morphology (in lime-
  stone operation)  to factors such  as pH, percent  solid oxidation,  slurry
  temperature, hold tank residence  time, make/pass, L/G,  and percent Cl  or
 Mg   in the  liquor.  No definite  correlations have been seen.  This fail-
 ure to observe such relationships, here and in the lime systems discussed
 above, is viewed to be a result of inadequate or insufficient data rather
 than a lack of such relationships.

      During the course of examination of samples received, a form of
 "mixed crystal" was observed occurring during the period January 1, 1976,
 to January 10,  1976, in both the TCA and venturi/spray tower systems and
 is shown in Figures 8 and 9.  The usual appearance of the mixed crystal
 is that shown in Figures 8A, 8C,  9A, and 9B where a sulfite rosette appears
 in intimate physical association with a well-developed,  although often
 imperfect, gypsum crystal.  The gypsum crystals often show a  large number
 of surface cracks and longitudinal crystal defects.   Enlarged  views of the
 areas  of contact between the two  forms show what appear  to be  CaSOg'O.SHgO
 plate  crystals  growing from  the body of the gypsum prism.   Figure  8B is
 such an enlargement  of a  contact  zone of the form shown  in 8A;  note also
 arrows in  Figures 8D,  9C,  and 9D.   Occurrence  of these "mixed  crystals"
 rarely has been  observed  in  samples other  than  those  included  in the time
 period quoted above  and in these  samples only  in minor (less than  5 per-
 cent)  quantities.  These  forms  may be related to  the  gypsum-calcium sulfite
 hemihydrate solid solutions  discussed by Borgwardt.1   Comparison of sample
 chemical composition and  scrubber  operating data  for  the period  of time
 during which  these samples were taken indicates  no excursions  from normal
 values which  might be  helpful in  explaining the  sudden appearance of these
 mixed  forms.  A possible  explanation  for the occurrence  of  the  "mixed"
 forms  is that the  severe  chemical,  pH, and thermal gradients present in a
 scrubbing  system provide an  excellent  environment for  the precipitation of
 disordered, nonequilibrium crystals.   Particularly under conditions of
 rapid precipitation and growth, crystals are easily formed having incor-
porated within their lattice ions  which  "do^not belong11 due to either
stoichiometric or  radius ratio effects (S03~ inclusions in a CaS04*2H20
lattice, for  example).  As a result of internal electrostatic forces,
these "foreign" ions will tend to migrate through the parent crystal

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 these  "foreign" ions will tend to migrate through the parent crystal
 lattice and, through a process of electrostatic segregation, form locally
 stable domains.  When these domains are on the surface of a crystal,
 changes in the liquor chemistry and temperature surrounding the parent
 crystal can cause this originally small domain to grow outward in the form
 of another, but related, chemical compound through natural processes of
 precipitation and, where useful, dissolution of the parent crystal.

     The occurrence of this process of exsolution and subsequent crystal
 growth on nucleation sites provided by surface domains is strongly sug-
 gested by the contact surfaces shown in Figures 8B, 9C, and 9D.


 Morphology of Accessory Components

     Under the general heading "accessory components" are included those
 materials which either are not directly involved in the desulfurization
 reaction or are present in such small quantities that their presence does
 not affect bulk sludge properties.

     Fly ash is the most important of the accessory components in sludge
 samples obtained in this study from normal operations, compromising 20 to
 40 percent by weight of the solids composition.  It is normally present
 in the form of featureless spheres ranging in diameter from submicron
 sizes up to those greater than 150 microns.  The spheres may be solid or
 hollow and consist of an amorphous aluminosilicate material usually con-
 taining calcium and/or iron.  A portion of the fly ash is magnetic and
 ranges in quantity from 5 to 60 percent by weight.  The presence of fly
 ash should exert some influence on liquor chemistry; samples of fly ash
 studied by other laboratories have shown neutralizing values of up to 4
 meq/g.7'8  A small fraction of the fly ash constituent is not spherical
 but appears as irregularly shaped vesicular particles.  Occasionally
 CaS03'0.5H20 plate crystals will be observed to have been precipitated
 on the surface of fly ash spheres.

     Gypsum (in unoxidized systems) and unreacted absorbent are generally
 observed in very small quantities (less than 5 percent total by weight).
 The CaS04-2H20 occurs primarily as broken and partially decomposed
 prisms (left center, Figure 3C) or as twinned forms (Figure 5B).   Unreacted
 absorbent will be seen as partially or almost completely dissolved irregu-
 lar forms (right center, Figure 5A and bottom center, Figure 7B).   Unburned
 coal and quartz are sometimes present in small amounts.


 Morphology of Solids Formed Under Forced Oxidation

     During the first quarter, 1977, forced oxidation tests were conducted
 by installation of an air sparger and accessory reaction tanks in the
venturi scrubbing train.  The results of this modification may be seen in
Figure 10 in which micrographs of solids from analysis points 1816 (spray
 tower hold tank,  no oxidation) and 1815 (venturi reaction tank, oxidation)
 are shown for comparison.  Where forced oxidation has been used (Figures
 8B, 8D, and 8F),  the primary reaction product appears as large, blocky

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gypsum crystals as compared to the much smaller single plates and open-
form aggregates (Figures 8A, 8C, and 8E) typical of routine limestone
operation.  The CaS04*2H20 crystals formed in this mode of oxidation
are often broken and twined, and range in size from 10 to greater than
100 microns.  Accompanying forms of CaSOs'O.SI^O are not observed.
     Accessory components of sludge produced in forced oxidation tests are
equivalent to those found under routine operation.

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                                Section 5

                        SLURRY SETTLING BEHAVIOR
     The settling behavior of slurries received during this study has been
determined by a static method.  The samples, approximately I liter in
volume, are transferred to 1-liter graduated cylinders (inside diameter of
6 cm and with a depth of 42 cm), mixed thoroughly by stirring and repeated
inversion of the cylinders, and then allowed to settle.  The height of the
solids-liquid interface is tabulated and plotted as a function of time.
The settled bulk density is calculated from Equation 1.
          n   - (B-A) - D(C-E)
          Psb ~       E
where:
     p ,  = settled bulk density, g/mL

     A   = weight of empty cylinder, g
     B   = weight of cylinder + slurry, g
     C   = initial volume of slurry, cm3
     D   = density of resulting supernatant fluid (after settling),  g/cm3
     E   = volume of settled slurry, cm3

The density measurement, D, was initially determined by liquid pycnometer
measurements of aliquots taken from various levels within the supernatant
liquor.  The results indicated that no detectable density gradient existed
within the liquid; therefore, all subsequent density measurements were
made with a hydrometer calibrated over the range 1.000 to 1.2000 g-cm"3.
The settled percent solids are calculated from Equation 2.


settled solids, % =

  (% solids in initial slurry) x (total wt. of slurry sample)
                   (weight of settled slurry)


The weight of the settled slurry, including entrapped liquor, is obtained
by subtracting the weight of the supernatant liquor (obtained by density
and volume measurements) from the total weight of the slurry sample.

     Sludge settling rates are known to be a function of temperature,
increasing temperature causing an increase in settling rate.  However,
because of temperature gradients existing within the scrubber process
train and seasonal variations in clarifier temperatures, all settling
tests in this study were performed at room temperature.

     The sedimentation behavior of particulate (nonflocculant) slurries
may be described generally by three basic modes:  clarification, zone
settling, and compression; with clarification applying at low solids con-
centration and compression applying at very high percent solids.  In the
clarification mode, individual particles settle independently at constant
rates which are primarily dependent on particle size and shape (Stokes1
                                 10

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Law applies).  Considerable particle size classification occurs  with the
larger particles settling first and the smallest settling last.   In the
zone settling mode, the particles are conceived to be all locked into a
plastic structure with very little independent settling (results from
higher percent solids).  Here, the solids subside as a consolidated
structure so that ideally a single settling rate may be ascribed to all
particles; this settling rate will be a function of solids concentration
although individual particle morphology may play a part because  of its
effect in determining the degree of porosity of the consolidated structure.
Ultimately, with very high solids concentration or towards the end of any
static settling test, the regime of compression settling will be reached.
In this mode, the hydrostatic bearing capacity of the settled solids,
including entrapped liquor, is assumed to be approximately equal to the
load produced by the settled solids plus any overlaying liquid.   Under
these conditions, subsequent subsidence will occur primarily through the
formation of dewatering channels or the rake action at the bottom of a
clarifier.

     Under average conditions in this study (limiting cylinder diameter,
static settling, 12 to 25 percent solids in slurry), zone settling most
often applied in that there was very little particle size or shape classi-
fication during settling; i.e., the entire body of solids settles simul-
taneously by dewatering.  There was very little free particle settling.
Rather, all particles settle together, their combined weight gradually
forcing the water contained within the slurry past them to the top of the
interface.  As the settling slurry approaches the compression stage,
"dewatering channels" were seen in cross section through the glass cylin-
der walls.  These channels gave the appearance of dendritic or tree-like
structures arising from many small channels at a depth of 7 to 8 cm.
beneath the interface and graually coalescing into a single channel which
allowed the water to escape from the settling solids.

     As slurry solids content decreases below 10 percent, clarification-
type settling is seen and individual particles settle according to their
own size and weight.  The average settling rate is very rapid (2 to 10
times faster than with slurries containing 15 to 25 percent solids), and
the solids-liquid interface is quite indistinct, often definable only
after compression settling is approached.

     Settling rates for solids of similar particulate morphology are
generally dependent on solids concentration.  Slurries with high solids
concentrations settle more slowly.  This may be illustrated with reference
to Figure 11A in which the settling rates for some limestone slurries are
shown by a plot of interface position as a function of time.  Individual
curves are labelled  for sample identification and original slurry percent
solids.  Thicker (higher solids concentration) slurries have lower settling
rates and take longer to reach the compression stage.  Slurry settling rate
behavior is complicated by the fact that the solids component morphology
can exert a strong influence.  As an example of this effect, behavior of
slurries obtained from the TCA system on May 14,  1976, and April 12, 1976,
(Figure 11B) may be compared.  Although the solids content by weight in
both slurries are essentially the same, the April sample settles more than
three times as fast and attains, when settled to  compaction, an ultimate
solids content of 68 percent  compared to 38 percent for the May sample.


                                  11

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 Inspection  of  the micrographs  of  these  solids  (Figure  12)  reveals  that
 while  both  contain  a predominance of  single plates,  the May  sample consists
 primarily of very small plates and plate  fragments.  These smaller parti-
 cles inhibit settling  and  entrap  more liquor upon  reaching the compression
 stage  due to a higher  degree of inter-particle  contact and sample  surface
 area.  This in turn limits the amoung of  liquor that may flow past parti-
 cles during settling and increases the  difficulty  with which dewatering
 can occur upon reaching the compression stage.

     The general relationship between sludge settling rate and percent
 solids for all samples included in this study is shown in Figure 13.
 To illustrate the differences in  settling rates caused by solids morpho-
 logy,  lime slurries (spherical aggregates) are  indicated by  the character
 "o," limestone slurries (plates)  by a "D," and  slurries obtained during
 forced oxidation tests (blocky gypsum crystals) by an "x."   In the  range
 10 to  25 percent solids, both lime- and limestone-derived slurries  show
 essentially the same linear, inverse  relationship  to settling rate.  On
 entering the regime of clarification  settling,  however, the  behavior of
 the two types of slurries differs.  The hydrodynamically preferable
 spherical forms precipitated with lime  scrubbing demonstrate more  rapid
 size classification and less hydrodynamic drag  during settling than do
 the plates or open aggregates of  limestone operation and, therefore, show
 a more rapid increase in settling rate within the  same range of solids
 content.  The gypsum slurries produced under conditions of forced  oxidation
 settle at the noticeably faster (5 to 10  times) rate than the other slur-
 ries even though the slurry solids content enforces  zone settling.  The
 crystals' very large size forms a  settling structure which is relatively
 open to water and thus allows less hindered settling although independent
 settling of particles will not be  allowed.  The greater degree to which
 these slurries may be dewatered is reflected in the  observation that the
 slurry produced with no oxidation  settles to a  final solids  content of
 23 percent with a bulk density of  1.17, while the  gypsum slurry settles
 in a much shorter time to a final  61 percent solids  and bulk density of
 1.55.

     Figure 14 shows the relationship between the bulk density of the
 settled slurries and their settled solids content.    An approximately
 linear, positive relationship is  seen between these  two properties.  Lime
 and limestone slurries show essentially the same behavior.

Fly ash-free test runs on both the TCA and venturi/spray tower systems
 during this study provided data on slurry properties which may be com-
pared with that derived from normal operations.  Based on these data, the
absence of fly ash has not clearly shown any effect  on sludge property
 relationships as shown in Figures  13 and  14.  In Figure 15 are shown the
 frequency distributions for the values obtained for  the settled solids
 content of lime and limestone slurries and for  all slurries taken from
 fly ash-free (<10 percent ash) runs.   While both lime- and limestone-
derived slurries exhibit essentially the same behavior, the slurries con-
taining no fly ash seem to settle  to a slightly lower final solids content.

     Due to sample handling and shipping,  the static settling tests per-
formed at Muscle Shoals were conducted from 3 to 14  days after the samples
were taken from the process loop.   Settling tests conducted at the Shawnee


                                  12

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Test Facility, however, are generally performed within a short time after
acquisition.  In addition, settling data at Shawnee are generated by the
Dorr-Oliver method which differs from a static test in that the bottom of
the test cylinder contains a rake rotated at 1/6 rpm during the test.   In
order to compare data generated by the two methods and to evaluate possi-
ble effects caused by the delay in testing, a program of comparison tests
was conducted.  The results of this work are contained_in Table 3.  The
mean value of the difference in the two measurements, y, is 3.6 with a
standard deviation of 10.8; the standard error of y is 10.8/^26 or 2.12.
The t-distribution value for 25 degrees of freedom and 95 percent double-
sized confidence limit is 2.06, so the limits are 3.6 ± 2.06 x 2.12 or
7.96 to -0.76.  Based on this information, no bias is conclusively shown
between the two procedures.
                                  13

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                                Section 6

                    SOLIDS SURFACE AREA MEASUREMENTS
     The size, shape, and complexity of individual solid particles in the
scrubbing slurry are important in that these factors may influence or con-
trol processes such as chemical reaction, filtration, or dewatering rates.
An indirect indication of the average particle size and complexity of the
slurry solids is available in measurements of the solids surface area.
The equipment and methodology necessary to perform this measurement have
been developed and implemented for routine characterization of dried
scrubber solids.  The specific instrumental technique used is a nitrogen
desorption method based on a variation of the single point B.E.T. method
and is adequately described in the literature.2

     Previously dried samples are placed in glass U-tubes approximately
10 cm in length and swept for 1 hour with a purge gas (30 percent nitrogen
in helium) at a rate of 80 ml-min l, after which analysis is performed on
the sample without removing it from the tube.  Values for the surface area
(M2/g) of samples received during this period are reported in Tables 1 and
2.  This method yields a precision of better than 1 percent and an accuracy
of better than 5 percent.

     Figure 16 shows the frequency distribution of surface area values.
The solid lines show the results of all measurements, while the dashed
lines indicate measurements made under "fly ash-free" (ash <10 percent)
conditions.  Note that the average specific area for samples obtained dur-
ing lime scrubbing is greater than that measured for samples taken from
systems employing limestone.   This difference in surface area values
reflects the differences in average particle size and morphology in lime
and limestone slurries and correlates with the observation that lime slur-
ries are more difficult to dewater than limestone slurries.

     The frequency distribution of surface area values for fly ash-free
runs shows essentially the same form as displayed by all runs combined.
This indicates that the surface area component contributed by the fly ash
is not a critical factor in determining sludge characteristics.
                                 14

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                                Section 7

                   THERMAL ANALYSIS OF SCRUBBER SOLIDS
     Thermal analysis of selected dried scrubbing solids was employed
using differential scanning calorimetry (DSC) in the range 330° to 500°C.
This temperature range was selected in order to study the thermal dehydra-
tion of the CaS03*0.5H20 component.  It was felt that substitution of car-
bonate or sulfate into the sulfite structure would result either in a shift
of this compound's desolvation temperature away from the observed in the
pure state or in an increase in complexity of the normally straightforward
endothermic desolvation reaction.  All samples studied were analyzed using
a Perkin-Elmer DSC-2 differential scanning calorimeter.  The temperature
scan rate used was 10°C/min, and dry nitrogen at a rate of 20 mL/min was
used as the purge gas.  Prior thermal conditioning consisted of preheating
the samples (in the instrument) at a temperature of 330°C for a period of
15 min.  All samples were analyzed in nonvolatile sample pans (small
aluminum containers of approximately 0.25-in. diameter and 0.125-in. depth,
with aluminum cover discs lightly crimped in place to prevent sample loss
but not hermetically sealed).

     Two types of thermal activity were observed.  The type of behavior
illustrated in Figure 17A has been observed to predominate in samples
taken from lime-scrubber systems.  Here a generally straight-forward endo-
thermic desolvation of the sulfite occurs only after an initial reaction
which may represent a gradual desolvation or decomposition of an unknown
compound.

     Figure 17B shows a type of thermal activity which is representative
of limestone systems.  In this case no initial thermal activity is seen,
but the endothermic reaction attributed to the sulfite decomposition
clearly consists of at least two components, although inadequately resolved.
The dashed curve superimposed on Figure 17B shows the thermogram produced
by the thermal decomposition of pure CaS03'0.5^0 prepared in our
laboratory.

     Thermal analysis of lime/limestones scrubbing materials has been
reported previously.3  In these studies, synthetic scrubbing solids were
prepared by the addition of fly ash to mixtures of the pure components
normally found in such sludges (CaS03*0.5H20, CaS04'2H20, CaC03, etc.)
These mixtures were studies by differential thermal analysis (DTA) and
thermogravimetric analysis (TGA).  The CaSOa'O.S^O was found to undergo
dehydration in the region 350° to 410°C.  This compares favorably with
our results which indicate an average decomposition temperature of approxi-
mately 390°C.  These values represent a deviation from the dehydration
temperature of 367°C for the pure compound as reported by Schropfer4
utilizing DTA.  DSC investigation of the pure compound prepared in TVA's
laboratory indicates a decomposition temperature of 364°C.

     It is not clear which aspects of the complex thermal behavior of the
samples examined to date are a result of matrix effects and which may be
assigned to reactions of carbonate- or sulfate-substituted CaSOs'
species.  An attempt was made to clarify this situation by using
                                 15

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 H20-saturated  N2  as  the purge  gas.   Ideally  an  increase  in the partial
 pressure  of  H20 in the gas  environment  surrounding  the sample should have
 displaced the  dehydration temperature of  CaS03'0.5H20.   This effect was
 not  observed due  to  instrument noise caused  by  microdroplets of water in
 the  gas stream.

      The  primary  purpose of this  study  was to show  any relationship
 between the  dehydration temperature  of  CaS03*0.5H20 and  other indicators
 of structure perturbation (optical index  of  refraction,  length of crystal-
 lographic unit cell  axes as determined  by x-ray diffraction, etc.).  Ther-
 mal  analysis of 57 samples  did not show any  definite relationship between
 the  desolvation temperature of the hemihydrate  and  any other indicator of
 crystal structure perturbation.   The reason  for apparent failure to show
 any  defined  relationship is attributed  to lack  of adequate precision in
 both thermal and  crystallographic data, although the former is likely to
 play the  major role.  Data  obtained  from  these  experiments are shown in
 Table 4.

      As an offshoot  of this work, a  simple and  rapid method for determina-
 tion of CaS04'2H20 in scrubber solids was developed.  It was shown that
 the  peak  area  resulting from gypsum  dehydration is  directly and linearly
 proportional to the  percent of gypsum in  the sample5'6 (in DSC, peak area
 is proportional to the AH of reaction).   This peak  is not obscured or
 interfered with by other components  in  the sample matrices studied and
 thus  provides  a clear-cut distinction between gypsum S04~ and substituted
 804   within  the sample.  Over  the range 10 to 0.3 percent gypsum, determi-
 nations may  be made  with a  precision of better  than 5 percent and an
 accuracy  of  better than 5 percent.

      Calibration  standards  over the  range 0.06  to 10 percent were prepared
 by adding pure gypsum to a  matrix prepared by batch heating a selected
 dried scrubbing sludge (original composition:   35 percent ash,  12 percent
 CaC03, 42 percent CaSOs'O.SI^O, and  10 percent  gypsum) at a temperature
 of 200°C  for 24 hours.  Examination  of this reference matrix by infrared,
 x-ray diffraction, DSC, arid optical microscopy  after heating revealed no
 trace of  residual gypsum.    Samples of scrubber  solids to be analyzed were
 dried at  a temperature of 50°C (in the instrument)  to a constant baseline
 to remove surface-adsorbed H£0.  The previously prepared inert (over the
 temperature  range of interest) matrix was used  as a reference material.
 A temperature  scan rate of  10°C/min was used for both samples and unknowns.
 Samples of known materials were prepared by adding  known, weighed amounts
 of CaS04'2H20 to dried sludge  samples which had been found by x-ray, IR,
 and DSC to contain no gypsum.   These samples were analyzed and compared to
 the previously prepared calibration curve.  Results of this investigation
 are in Table 5.  While this procedure is  fairly accurate over the range 10
 to 0.5 percent (weight) gypsum, inaccuracy due  to difficulties  in preparing
 solid mixtures at these levels increases quickly below 0.5 percent.  The
method is easily extended to gypsum contents higher than 10 percent,
although  an inert diluent may be necessary above 20 percent gypsum.
                                 16

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                                Section 8

                          STATISTICAL ANALYSIS
     The statistical analysis of sludge data from the venturi/spray tower
and TCA systems centered on determining typical operating conditions for
the duration of the data and an examination of extreme results  (both high
and low) of settled bulk density, percent settled solids, and their asso-
ciated variables.  These variables were then examined for possible causi-
tive effects on settled bulk density and percent settled solids.   Estimates
of variation with regard to both typical and extreme operating  conditions
were made so significant changes in the response of settled bulk  density
and percent settled solids could be identified.  Nonlinear regression
models were developed which characterized the behavior of settled bulk
density and the percentage of settled solids.  Summary tables (6  to 10)
are presented for average and extreme values for all variables.

     In the presentation of these analyses, the total calcium content of
the sludge (that which is bonded to sulfite, sulfate, and carbonate) is
reported as CaO.  Also SQ%, SOa, and C02 represent the relative quantities
of sulfite, sulfate, and carbonate in the sludge.
Mean Values

     Mean values and standard deviations are presented in Table 6 for both
the lime and limestone product sludges studied over the test period.   Iden-
tification of high and low ranges of the variables are also presented.
For the lime product sludges, the following averages were seen:  oxidation,
20 percent; settled solids, A3 percent by weight; settled bulk density,
1.3 g/cc; and 10 percent solids recirculated.  The solids, by weight, had
an average composition of 32 percent fly ash, 29 percent CaO, 25 percent
sulfite, 7 percent sulfate, and 1.5 percent carbonate.  Averages of the
limestone product sludge data show 22 percent oxidation, 41 percent set-
tled solids, 1.3 g/cc settled bulk density, and 15 percent solids recir-
culated.  The average solids analysis is 33 percent fly ash, 30 percent
CaO, 21 percent sulfite, 6 percent sulfate, and 5.5 percent carbonate.
Percent Settled Solids

     The following mean values were associated with high levels (57.9 per-
cent) of settled solids for the lime product sludges:  high natural oxida-
tion, 38.6 percent; high percentage of solids recirculated, 14.5 percent;
high fly ash content, 39.5 percent; and low levels of calcium sulfite
solids, 18.6 percent.  Two samples under a program for forced oxidation
had oxidation in excess of 95 percent.  This was with an average of 18.6
percent solids recirculated, 55.7 percent fly ash, 0.5 percent sulfite
solids, and 65 percent settled solids.

     The limestone product sludges also had two groups of data with high
levels of settled solids.  One group had an average oxidation of 17.9
percent.  This group was characterized by 17.7 percent solids recirculated,
                                   17

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 a  fly  ash  content  of  38.6 percent, and settled solids of 53.2 percent.
 The  second group obtained during  forced oxidation testing had an average
 oxidation  of  98.3  percent with settled solids of 63.3 percent, fly ash
 content  of 64.5 percent, and extremely low sulfite solids of 0.2 percent.
 Table  7  summarizes the data characteristic of high settled solids.

     Low levels of settled solids were also examined for the lime and
 limestone  product  sludges to obtain further information on the behavior
 and  effects of variables associated with the percent of settled solids.
 The  lime product sludges had an average of 26.9 percent settled solids
 with mean  oxidation of 14.8 percent, 8.8 percent solids recirculated, fly
 ash  content of 17.0 percent, and a high level of sulfite solids of 25.2
 percent.   Also at high levels were CaO at 37.5 percent and carbonate at
 2.8  percent.

     The limestone product sludges exhibited similar behavior at low
 levels of  settled solids.  An average of 26.9 percent settled solids was
 associated with 15.6  percent oxidation, 9.2 percent solids recirculated,
 and  a  fly  ash content of 14.0 percent.  The solids were composed of 27.2
 percent  sulfite, 38.8 percent CaO, and 7.2 percent carbonate.  Table 8
 summarizes the low settled solids characteristics.
Settled Bulk Density

     Analysis of factors associated with settled bulk density indicated
the effect of high oxidation versus low oxidation levels.  In general,
for the lime product sludges, a settled bulk density of 1.4 g/cc or more
was regarded as a "high" level.

     The following were average values associated with low levels of oxi-
dation (11.4 percent average):  settled bulk density, 1.43 g/cc; percent
recirculated solids, 7.6 percent; fly ash, 34.3 percent; CaO, 28.8 percent;
sulfite, 25.2 percent; and carbonate, 3.2 percent.  For the high oxidation
group with a mean oxidation of 96.6 percent, the associated values were:
fly ash, 55.7 percent; percent solids recirculated, 18.6 percent; sulfite,
0.5 percent; carbonate, 0.3 percent; and CaO, 15.6 percent.  For this high
oxidation group, the settled bulk density was 1.65 g/cc.

     Settled bulk density for the limestone product sludges behaved simi-
larly.  An average settled bulk density of 1.43 g/cc was associated with
an oxidation level of 11.4 percent.  Typical average values for the other
variables were:  percent solids recirculated, 15.2 percent; fly ash, 32.4
percent; CaO, 30.5 percent; sulfite content, 24.1 percent; and carbonate
content, 4.8 percent.  The settled bulk density for the high oxidation
group was 1.61 g/cc with an average oxidation value of 98.3 percent.  The
other average values were:   fly ash, 64.5 percent; CaO, 12 percent; sul-
fite, 0.2 percent; carbonate, 0.7 percent; and 16.4 percent solids recir-
culated.   Table 9 summarizes the high settled bulk density data.

     In general, the lower settled bulk density for both lime and limestone
systems was associated with low oxidation, low fly ash content,  and a lower
than average percent solids recirculated.   At the same time high levels
                                 18

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of CaO, sulfite, and carbonate solids occurred.    Table  10  illustrates
the low settled bulk density data.


Relationships Found in the Data Using Regression Analysis

     The data were extensively examined for relationships between  the per-
centage of settled solids and settled bulk density and those  variables
which determine their behavior.  The two variables having the largest
effect on both settled solids and settled bulk density are  the percent
sulfite solids and percent solids recirculated.   The analysis resulted  in
equations which quantify the response of settled solids  and settled bulk
density to changes in the percent sulfite solids and percent  solids recir-
culated.  It must be noted that these equations  pertain  only  to the ranges
of data which occurred in this study.  The Equations are:


          Lime:  % settled solids = 39.6 X/0'09 X2°'15           (3)



                                  = i7.ixr°-09xs
                                                   0.09
     Limestone:  % settled solids =17.1 Xj'0'09 X2°'42          (5)
                              p .  = 1.15 Xj      X2
                              Ksb         *       £
where:  p ,  = settled bulk density, g/mL
         S D
        Xj  = wt. % sulfite solids
        X2  = wt. % solids recirculated

     As an example, Equation 5 for limestone product sludges  predicts  an
average of 40.9 percent settled solids for 21 percent sulfite solids  and
15 percent solids recirculated.

     % settled solids = 17.1(21.0)~°-09(15.0)0-42

In (% settled solids) = ln(17.1) - 0.09 1N(21.0) + 0.42 ln(15.0)

                      = 2.84 - 0.27 + 1.14 = 3.71

     % settled solids = exp(3.71) = 40.9%

     Table 6 indicates that this is a typical settled solids  figure.
Table 11 summarizes the change in settled bulk density and percent
settled solids for changes in percent sulfite solids and percent  solids
recirculated, using Equations 5 and 6.

     For a constant percent solids recirculated, raising the  sulfite  con-
tent of the sludge decreases both settled solids and settled  bulk density.
For a constant sulfite content, raising the percent solids recirculated
raises both the percent settled solids and settled bulk density.   The last
two entries in Table 6 illustrate the response of settled solids  and
settled bulk density to a combination of (1) low sulfite solids (0.4  per-
cent) and high solids recirculated (18.0 percent) and (2) a high  sulfite
solids (37.0 percent) and low solids recirculated (5.0 percent).   The low


                                 19

-------
 sulfite  solids with high solids recirculated results in a predicted high
 settled  bulk density of 1.61 g/cc and high settled solids of 62.5 percent.
 These predicted values correspond well to actual values of 1.65 g/cc and
 62.8 percent which occurred at 0.4 percent sulfite solids and 17.8 percent
 or  18.2  percent solids recirculated, respectively.  The case of high sul-
 fite solids and low solids recirculated indicates a low estimated settled
 bulk density of 1.20 g/cc and low settled solids of 24.3 percent.  Actually,
 a 1.16 g/cc settled bulk density occurred at 36.3 percent sulfite solids
 and 7.5  percent solids recirculated, while 24.9 percent settled solids was
 noted at 36.6 percent sulfite solids and 7.6 percent solids recirculated.
 The equations are seen to typify the behavior found in the data.  Similar
 calculations can be made for the lime system.

     A more detailed explanation of the derivation of the equations and
 the statistical analysis are presented in the next section.


 Regression Models - Statistical Considerations

     The behavior of the percentage of settled solids and settled bulk
 density  was further characterized by examining possible relationships with
 associated variables.  A nonlinear model best described the response of
 settled  solids and settled bulk density with the percentage of solids
 recirculated and calcium sulfite content of the solids being the indepen-
 dent variables.  The model is:

                  BI   82
          y = a Xi   X2  e                                       (7)

 where Y  is the dependent variable of percent settled solids or settled
 bulk density, Xj is the percent of sulfite solids and X2 is the percent
 of solids recirculated.   The unknown parameters to be estimated are a,
 B1} B2, with e being a random error.  The model can be linearized by
 taking natural logarithms which result in the following equation:

          In Y = Inof + B! InXj. + B2 lnX2 + Ine                   (8)

 which can be estimated by standard least squares analysis.  For valid
 tests of significance and confidence intervals, Ine must be N(0,Io2).
 Table 11 presents the estimates Inot, bi, and b2 of Inot, Bj, and B2 with
 the associated standard errors.   Extensive examination of the residuals
 did not indicate any model definciencies or violations of standard
assumptions necessary for least squares analysis.

     The resulting models are given by Equations 3, 4, 5, and 6 which are
shown on page 19.

     One indication of how well an equation fits the data is the multiple
correlation coefficient squared (R2).   It estimates the proportion of
total variation explained by the regression.   The F-value indicates how
significant, in a statistical sense, the coefficients are when taken all
together.  Table 13 summarizes the R2  and F values from the regression
analysis plus the antilogarithm of the standard error of estimates.
                                 20

-------
     Figures 18 through 29 show the graphs of observed values versus pre-
dicted values from the nonlinear models.   (For both limestone and lime and
the dependent variables of percent settled solids and settled bulk density).
Three types of graphs are plotted:  (1) dependent variable versus percent
calcium sulfite solids, (2) dependent variable versus percent solids recir-
culated, and (3) observed dependent variable versus the predicted dependent
variable at the same values of the independent variables.

     For example, Figures 18, 19, and 20 for limestone show how the per-
cent settled solids decline as a function of percent calcium sulfite
solids and increases as a function of percent solids recirculated, and
that the regression equation does fairly well in predicting the response
of percent settled solids.  Examination of the other figures indicates
that the regression equations model the data well for the limestone
system, but not quite as well for the lime system.
                                  21

-------
                               REFERENCES


1.   Borgwardt, R. H., "Limestone Scrubbing  of S02  at  EPA  Pilot  Plant,"
     EPA Progress Report, June 11,  1973.

2.   Nelsen, F. M. and F. T. Eggertsen, An_alJ_Chem_1  30,  8  (1958).

3.   Taylor, W. C.  Combustion_45 (4),  1522  (1973).

4.   Schropfer, V. L. , Zeitschr_ift__fiir_  Ajior^a£i^h£_urui_AJJ^enuMne Chemie
                               "         -       .      -
                               ____             __^
     4CM (1), 114 (1973).      "        -       .      -

5.   Schlichenmaier, V., Thermochemica Acta  11, 334-338  (1975).

6.   Kuntze, R.  A., Materi al s JRes_. _and__S_t d s^ , 640-642  (August  1962).

7.   Martens, D. C., Com^qst__Science_ 12 (6), 15-19 (1971).

8.   Martens, U. C., M. G. Schnappinger , and L. W. Zelazny, "The Plant
     Availability of Potassium in Fly Ash," Soil Science Society of
     America Proceedings, 34, 453-456 (1970).
                               FIGURE  1
Photomicrographs  illustrating  various  forms  in  which CaS03'0.5H20 is
found in scrubber sludge.

     A.   Typical well-formed  single sulfite  plates  formed when
          limestone is used as  the  absorbent

     B.   Typical well-formed  single sulfite  plates  formed when
          limestone is used as  the  absorbent

     C.   Open form of aggregate  sulfite  crystal  formed  when  limestone
          is used as the absorbent

     D.   Aggregated form of sulfite crystal  (rosette) formed when
          limestone is used as  the  absorbent

     E.    Typical spherical aggregates of  sulfite  crystals formed when
          lime is used as the absorbent

     F.   Typical spherical aggregates of  sulfite  crystals formed when
          Lime is used as the absorbent
                                 22

-------

Figure 1A
Figure 1B

Figure 1C
Figure 1D
Figure 1E
 Figure IF
                                   23

-------
                               FIGURE 2
Photomicrographs of CaSOs'O.Sh^O aggregates formed when lime is used as
the absorbent.

     A.    Spherical sulfite aggregates formed when using lime as the
          absorbent on 4/11/75

     B.    Spherical sulfite aggregates formed when using lime as the
          absorbent on 4/11/75

     C.    Spherical sulfite aggregates formed when using lime as the
          absorbent on 9/28/75

     D.    Spherical sulfite aggregates formed when using lime as the
          absorbent on 9/21/75

     E.    Spherical sulfite aggregates formed when using lime as the
          absorbent on 10/5/75

     F.    Spherical sulfite aggregates fomred when using lime as the
          absorben on 9/28/75
                                 24

-------
                    rv         *
Figure 2A
Figure 2B
Figure 2C
Figure 2D
Figure 2E

-------
                               FIGURE 3
Photomicrographs of CaS03'0.5H20 plates formed when limestone is used
as the absorbent.

     A.    Flat sulfite plates formed when using limestone as the
          absorbent on 10/21/75

     B.    Flat sulfite plates formed when using limestone as the
          absorbent on 10/12/75

     C.    Flat sulfite plates formed when using limestone as the
          absorbent on 11/6/75

     D.    Flat sulfite plates formed when using limestone as the
          absorbent on 10/28/75

     E.    Flat sulfite plates formed when using limestone as the
          absorbent on 11/19/75

     F.    Flat sulfite plates formed when using limestone as the
          absorbent on 11/19/75
                                 26

-------
Figure 3A
Figure 3B
Figure 3C
Figure 3D

Figure 3E
Figure 3F
                             27

-------
                               FIGURE 4
Photomicrographs of CaS03'0.5H20 aggregates formed when lime is used as
the absorbent.

     A.    Spherical sulfite aggregates formed when using lime as
          the absorbent on 2/15/76

     B.    Spherical sulfite aggregates formed when using lime as
          the absorbent on 2/15/76

     C.    Spherical sulfite aggregates formed when using lime as
          the absorbent on 2/21/76

     D.    Spherical sulfite aggregates formed when using lime as
          the absorbent on 2/21/76

     E.    Spherical sulfite aggregates formed when using lime as
          the absorbent on 3/2/76

     F.    Spherical sulfite aggregates formed when using lime as
          the absorbent on 3/2/76
                                 28

-------
Figure 4A
Figure 4B
Figure 4C
Figure 4D
Figure 4E
Figure 4F
                               29

-------
                               FIGURE 5
Photomicrographs of CaS03'0.5H20 plates formed when limestone is used
as the absorbent.

     A.    Flat sulfite plates formed when using limestone as the
          absorbent on 3/28/76 (note:   unreacted absorbent — right
          center)

     B.    Flat sulfite plates formed when using limestone as the
          absorbent on 3/14/76 (note:   twinned form of gypsum
          crystal — right center)

     C.    Flat sulfite plates formed when using limestone as the
          absorbent on 4/3/76

     D.    Flat sulfite plates formed when using limestone as the
          absorbent on 3/20/76

     E.    Flat sulfite plates formed when using limestone as the
          absorbent on 4/21/76

     F.    Flat sulfite plates formed when using limestone as the
          absorbent on 4/21/76
                                 30

-------

Figure 5A
Figure 5B


Figure 5C
 Figure 5D

Figure 5E
                                31
 Figure 5F

-------
                               FIGURE 6
Photomicrographs of CaS03'0.5H20 aggregates formed when using lime
as the absorbent.

     A.    Spherical sulfite aggregates formed when using lime as
          the absorbent on 5/15/76

     B.    Spherical sulfite aggregates formed when using lime as
          the absorbent on 5/8/76

     C.    Spherical sulfite aggregates formed when using lime as
          the absorbent on 6/9/76

     D.    Spherical sulfite aggregates formed when using lime as
          the absorbent on 5/31/76

     E.    Spherical sulfite aggregates formed when using lime as
          the absorbent on 6/27/76

     F.    Densely  inter-penetrating  (aggregates)  sulfite plates
          formed under  elevated  levels of  chloride ion  (2.13  wt
          percent)  when using  lime as  the  absorbent  on  6/20/76
                               32

-------
Figure 6A
Figure 6B
                                                  1816  5/31/76 8738
                                                    Figure 6D
Figure 6E
Figure 6F
                              13

-------
                               FIGURE 7
Photomicrographs illustrating the relationship between
plate size and scrubber system Ca:S stoichiometry with limestone as
the absorbent.

     A.    Flat sulfite plates formed when using a Ca:S stoichiometry
          of 0.98

     B.    Flat sulfite plates formed when using a Ca:S stoichiometry
          of 1.06

     C.    Flat sulfite plates formed when using a Ca:S stoichiometry
          of 1.13

     D.    Flat sulfite plates formed when using a Ca:S stoichiometry
          of 1.27

     E.    Flat sulfite plates formed when using a Ca:S stoichiometry
          of 1.43

     F.    Flat sulfite plates formed when using a Ca:S stoichiometry
          of 1.63
                                 34

-------
   Figure 7A
  Stoic.=0.98
  Figure 7C
 Stoic.= 1.13
   Figure 7B
 Stoic.= 1.06
  Figure 7D
 Stoic.-1.27
 Figure 7E
Stoic.=1.43
 Figure 7F
Stoic.= 1.63

-------
                               FIGURE 8
Photomicrographs of "Mixed Crystal" forms.

     A.    Sulfite rosette in intimate physical association with a
          well-developed gypsum crystal

     B.    Enlargement of a contact zone of the sulfite rosette and
          gypsum crystal of the form shown in A

     C.    Sulfite rosette in intimate physical association with a
          gypsum crystal

     D.    Contact zone of sulfite and gypsum mixed crystal (note:
          arrow)
                                  36

-------
,1
                                                        ^F          Sfc
                      Figure 8A
Figure 8B

                     Figure 8C
Figure 8D

-------
                               FIGURE 9
High-magnification photomicrographs of sulfite-gypsum "Mixed Crystal"
forms.

     A.   Sulfite rosette in intimate physical association with a
          well-developed gypsum crystal

     B.   Sulfite rosette in intimate physical association with a
          well-developed gypsum crystal

     C.   Contact zone of sulfite and gypsum mixed crystal (note:
          arrow)

     D.   Contact zone of sulfite and gypsum mixed crystal (note:
          arrow)
                                 38

-------
Figure 9A
Figure 9B
Figure 9C
Figure 9D

-------
                               FIGURE 10


Photomicrographs of sludge solids components with and without forced
oxidation on the same system (venturi/spray tower).

     A.    Flat sulfite plates formed with no forced  oxidation in the
          spray tower

     B.    Gypsum crystals formed with forced oxidation in the venturi

     C.    Enlargement of the sulfite plates shown in A

     D.    Enlargement of the gypsum crystals shown in B

     E.    High-magnification of the sulfite plates shown in A

     F.    High-magnification of the gypsum crystals  shown in B

-------
Figure 10A
 Figure IOC
                                                      Figure 10B
                                                        Figure 10D
  Figure 10E
                                                         Figure 10F

-------
 36
                100
                          400
             500
                               200           300
                                 Time, min.
Figure 11A.  Similar particulate morphology but different slurry percent solids

                                            T
                 100
200          300
   Time,  min.
400
                                                                       500
Figure 11B.  Different particulate morphology but similar slurry percent solids

                Figure 11.  Slurry settling rate curves

                                    43

-------
                               FIGURE 12
Photomicrographs of solids producing settling behavior shown in Figure
11B.

     A.    Small sulfite plates and plate fragments in TCA scrubbing
          slurry sample of 5/14/76

     B.    Large sulfite plates in TCA scrubbing slurry sample  of
          4/12/76
                                 44

-------
Figure 12A
Figure 12B
   45

-------
120r-
                       •  Lime

                       D  Limestone
                       X  Oxidation
1004
 80
 60
                               •   •
 40
                                                            X X

                                                            X

                                                            x
 20
                                   •  •     •
    0
                        00      D  •   •o
                       0 00    •    •  «0 •
                            •  0  0 »0  0
                           •         •    0

                      1  	  	   1
                 0 0    •• 0          •
         00   000 0« 00000  •   D     0
             o 000 ooo •onn   oo      o
           oo    o« o OKID o  oo   o  o

                  I	1
10
                                                          15
20
                                                      25
                                                                                                                30
                                              Solids Content, % (wt)


                         Figure 13.  Settling rate of lime and limestone scrubber slurries

-------
1.7
1.6
1.5
                  •  Lime

                  D  Limestone
                  X  Oxidation
                                                                                  XX
                                                                                   X
                                                                                  X
1.4
1.3
1.2
                                        ODD*
                                    •      o  on  M
                                         a D »a   •
                                  •  •a o* a* a«a ••
                               ••CD*    D*D •  a • Q
                                    MOMOOD*   •
                                   • ••a     *o
                           D  DODO  oa« • a            •
                       D    D D 0    DO      •
                           0         •    •
                          a*  an
                     a • o      «o»           a
                               a
                            D D  DO
                                •0
                                 D
           0

           a
1.1
    10
20
50
                  30                 40


                     Settled Solids Content,  % (wt)


Figure 14.  Settled bulk density for lime and limestone  scrubber slurries
60
70

-------
   40
      T
          • All limestone runs

          0 All lime runs


          D All flyash free runs
   30
C/)



O



QJ
O


-------
40
1 1 1 1 1 1 1 1 1 1
0 All limestone runs
1 1
                                            O  All lime runs
                                            •  Flyash free limestone runs
                                            [3  Flyash free lime runs
            -
                                 A      5       6      7      8
                                    Surface Area Value  (ra2/g)
10
11
12
           Figure  16.   Distribution  of  surface  area values  for  solids produced  under
                       lime,  limestone,  and  fly ash-free  operation

-------
CJ
0)
co
00
0)
•o
4-1
•rl
>
•rl
4J
•H
CO


-------
  o
  o
  O
  o
  to
  o
  o

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  10
 0) O
 ?  •

^ o.
s^ *
O O
co o
CO
   O
   O
   o
   o
   
-------
o
o
                                  NON-LINEAR MODELS



                                  (ORIGINAL SCALE)



                                    0 - Observed



                                    * - Predicted
                             
-------
o
o
                                  NON-LINEAR MODELS



                                  (ORIGINAL SCALE)
                                                PREDICTED=OBSERVEO
             2:3.00     3\ .0039.00      47.00      55.00

                       Observed Value of Settled Solids, % (wt)
63.00
71 .00
         Figure 20.  Predicted  and observed final settled solids  content for lime-

                    stone scrubber slurries
                                       53

-------
o
CD
                    NON-LINEAR MODELS

                    (ORIGINAL SCALE)

                       0 - Observed

                       * - Predicted
              ©
              s
              I
                                            
-------
                                       NON-LINEAR MODELS


                                       (ORIGINAL SCALE)


                                          0  - Observed


   °                                     *  - Predicted
   o
   r-
                                                    
-------
o
oo
o
CO
                                  NON-LINEAR MODELS


                                  (ORIGINAL SCALE)
                                                PREDICTED=OBSERVED
 1 .10
1.20       1.30      1.40       1.50       1.60
          Observed Value of Settled Bulk Density g/cc
1.70
1.80
         Figure 23.   Predicted and observed settled bulk density for limestone

                     scrubber slurries
                                       56

-------
o
o
                                    NON-LINEAR MODELS



                                    (ORIGINAL SCALE)



                                       0 -  Observed



                                       * -  Predicted
               ©
                                             O


                                    O    0  (D
                                        
-------
                       NON-LINEAR MODELS

                       (ORIGINAL SCALE)

                          0 -  Observed

                          * -  Predicted
                                          ©   ©
                                              x
                                                 ©
       ©                             ©
                      ©
                      ©

                                            ©                    *
                                    *«r *«
                                  w  M^^
                                  ©
                                                                 ©
            *li »*•»"<..
    ©ffi
                                    ©
            o
                 ©
  4.00       8.00       12.00      16-00      20-00      24.00      28-00
                     Solids Recirculated, % (wt)

Figure 25.  Final settled solids  content of lime scrubber slurries as a
           function of recirculated solids content
                               58

-------
                                 NON-LINEAR MODELS



                                 (ORIGINAL SCALE)
o
o
                                                PREDICTED=OBSERVEO
  15.00
23.00
          Figure 26.
31.00     39.00     47.00     55.00

Observed Value of Settled Solids, % (wt)
63.00
71.00
        Predicted and observed final settled solids content  for lime

        scrubber slurries

-------
 o
 CO
  o
  CD
o
o
 :sj
 j-i
en
a)
P
 3

Pd
                                     NON-LINEAR MODELS



                                     (ORIGINAL SCALE)



                                        0 - Observed



                                        * - Predicted
                                    
-------
o
CO
                                  NON-LINEAR MODELS


                                  (ORIGINAL SCALE)


                                     (!) -  Observed


                                     * -  Predicted
                          (53
                *K,
                            CD ffl
                             (0  O

                              O
                                                          
-------
                                   NON-LINEAR MODELS


                                   (ORIGINAL SCALE)
  o
  CD
  o
  r-
o
CJ
•H
CO
C
OJ
s -
13
0)
M
P-i
  O
  CM
                                                   PREDICTED=OBSERVED
               1.20


            Figure 29
   1.30      1.40       1.50       1.60
 Observed Value of Settled Bulk Density, g/cc

Predicted
slurries
                                   1.70
1.80
°bSerVed S6tUed bulk density of lime scrubber
                                          62

-------
                                                      TABLE 1.   TCA SLURRY ANALYSES
U>
RUN NUMBER 539-2A
ANALYSIS POINT 2816
DATE 031375
TIME 1300
ADSORBENT LS
ON-SITE SOLIDS ANALYSES
ASH (MT ft) 28.81
CA (MT ft) 31.33
S02 (MT ft) 15.81
S03 (MT ft) 7.08
CO? (MT ft) 11.36
TVA SOLIDS CHARACTERIZATION
ASH (MT ft* ACID INSOLUBLE) 25.0
CACO3 (MT ft* BY IRI 32.0
CAS03 X .5 H20 (MT ft, IR) 36.0
CAS04 X 2H20 (MT ftt IR) 6.8
SURFACE AREA (SO M/GH) 3.8
TVA SLURRY CHARACTERIZATION
SLURRY SOL I OS ft 15.5
SETTLED ft SOLIDS 44.7
SETTLED BULK DENSITY (GM/CC) 1.22
SETTLING RATE (CM/HR) 5.0
TVA CRYST ALLOGRAPH 1C ANALYSES
SULFITE REFRACTIVE INDEX 1.590
SULFITE A AXIS 9.790
STD. ERROR 0.017
SULFITE B AXIS 10.678
STO. ERROR 0.010
SULFITE C AXIS 6.503
STD. ERROR 0.008
SCRUBBER OPERATIONAL PARAMETERS
ft SOLID OXIDATION 26.40
SAT. RATIO (RADIAN 50 C.) 0.0
STOIC. RATIO 1.67
SLURRY PH 6.00
SLURRY TEMPERATURE (C) 50.0
HAKE/PASS ( MOLES/ THOUS GAL) 0.0
LIQ/GAS (6AL/THOUS CFM) 0.0
MT ft CL IN LIQUOR 0.19
MT ft MG IN LIQUOR 0.03
HOLD TANK RES. TIME (WINS) 25.0
539-2A
2616
031475
1300
LS

27.43
31.36
16.11
6.05
11.25

33.0
28.0
39.0
0.0
4.4

13.5
35.6
1.24
4.7

1.590
9.798
0.016
10.661
0.009
6.492
0.008

0.0
0.0
1.56
6.00
52.0
0.0
0.0
0.16
0.03
25.0
54 1-2 A
2816
032675
1500
LS

23.47
34.96
15.91
8.11
12.06

29.0
33.0
29.0
8.7
3.5

13.9
34.3
1.25
3.4

1.591
9.760
0.028
10.640
0.014
6.491
0.012

28.90
1.08
1.76
5.85
52.0
0.0
0.0
0.15
0.03
15.0
546-2A
2816
061175
1500
LS

47.53
23.92
19.03
3.46
2.55

43.3
11.6
34.7
10.4
2.8

14.9
44.9
1.30
6.6

1.590
9.795
0.006
10.695
0.007
6.551
0.004

12.70
1.21
1.25
5.70
50.0
60.0
33.4
0.33
0.02
15.0
546-2A
2816
061275
0700
LS

38.72
25.84
22.05
4.42
3.78

43.3
13.3
32.1
11.3
2.6

15.9
38.8
1.26
4.8

1.590
9.790
0.010
10.694
0.012
6.518
0.010

13.80
1.10
1.15
5.65
52.0
86.5
34.1
0.26
0.03
15.0
546-2A
2616
061775
0700
LS

29.55
30.18
25.95
3.66
5.21

26.7
16.9
48.0
8.4
2.5

15.6
40.6
1.32
5.3

1.593
9.800
0.015
10.689
0.014
6.515
0.012

10.10
0.40
1.14
5.95
50.0
107.4
33.9
0.20
0.03
15.0
557-2A
2816
080875
1426
LS

39.55
27.05
14.80
5.61
8.50

42.0
14.6
32.5
10.9
2.4

15.5
46.7
1.32
7.3

1.591
9.791
0.009
10.730
0.010
6.517
0.008

23.27
0.97
1.60
5.95
54.0
83.5
40.9
0.18
0.03
15.0
559-2A
2616
091475
0700
LS

35.62
28.93
17.30
4.95
8.66

35.0
20.1
35.9
9.0
3.7

16.2
39.9
1.30
4.3

1.589
9.766
0.006
10.700
0.008
6.520
0.006

18.60
0.46
1.55
6.05
52.0
85.9
40.3
0.16
0.03
15.0
5S9-2A
2816
092175
0700
LS

38.08
27.89
15.01
5.84
8.65

30.0
18.1
42.2
9.7
2.8

16.1
39.6
1.28
4.7

1.591
9.767
0.003
10.697
0.005
6.517
0.004

23.70
0.43
1.62
5.40
53.0
92.8
40.0
0.19
0.04
15.0
560-2A
2816
092875
0700
LS

32.34
30.29
21.32
3.70
7.78

35.7
35.7
30.7
8.4
3.4

9.7
35.8
1.24
7.9

1.590
9.792
0.017
10.693
0.012
6.510
0.010

12.10
0.37
1.42
5.70
50.0
0.0
42.0
0.17
0.04
15.0
561-2A
2616
100575
0700
LS

31.98
28.73
22.42
5.02
6.13

29.0
16.1
46.2
8.7
2.5

15.1
40.9
1.26
5.8

1.589
9.797
0.006
10.697
0.006
6.514
0.005

15.10
0.35
1.24
5.95
50.0
89.8
40.0
0.0
0.0
15.0
S62-2A
2816
101275
0700
LS

28.39
30.42
20.16
7.43
7.26

26.0
18.6
45.6
7.7
2.7

15.3
39.6
1.29
5.0

1.590
9.794
0.006
10.697
0.006
6.514
0.005

22.60
0.49
1.33
5.85
54.0
79.2
40.5
0.22
0.03
12.0
562-2A
2816
102175
0700
LS

33.68
31.20
18.62
6.12
6.15

29.0
21.3
41.2
8.5
3.5

14.2
39.4
1.2S
4.6

1.589
9.768
0.007
10.702
0.-007
6.512
0.005

20.80
0.0
1.52
5. SO
50.0
84.6
40.3
0.0
0.0
12.0
     LS =  Limestone

-------
                                  TABLE 1.  TCA  SLURRY ANALYSES
RUN NUMBER  562-2A   562-2A  563-2A  564-2A  565-2A   567-2A   568-2A  570-2A  571-2A  566-2B   575-2A  5T7-2A  579-2A
ANALYSIS POINT 2816
DATE 102875
TIME 0900
ADSORBENT LS
ON-SITE SOLIDS ANALYSES
ASH (tfT %) 29.58
CA (NT «) 32.78
S02 (NT ft) 20.53
S03 (NT %) 3.06
C02 (NT %) 10.10
TVA SOLIDS CHARACTERIZATION
ASH (NT %, ACID INSOLUBLE) 27.0
CAC03 (HT *t BY IR) 29.2
CAS03 X .5 H20 (HT %• IR) 38.7
CAS04 X 2H20 (NT *. IR) 5.1
SURFACE AREA (SO M/GM) 2.4
TVA SLURRY CHARACTERIZATION
SLURRY SOLIDS % 21.9
SETTLED * SOLIDS 45.2
SCTTLED BUCK DENSITY (GM/CCI 1.35
SETTI ING RATE (CM/HR) 3.6
TVA CRYSTAU-OGRAPHIC ANALYSES
SULFITE REFRACTIVE INDEX 1.590
SUtFITE A AXIS 9.802
STO. ERROR 0.005
SULFITE 8 AXIS 10.683
STD. ERROR 0.005
SULFITE C AXIS 6.506
STO. ERROR 0.004
SCRUBBER OPERATIONAL PARAMETERS
% SOLID OXIDATION 10.60
SAT. RATIO (RADIAN 50 C.) 0.19
STOIC. RATIO 1.63
SLURRY PH 5.82
SLURRY TEMPERATURE (d 51.0
MAKE/PASS (MOLES/THOUS GAL) 86.6
LIO/GAS (GAL/THOUS CFM) 40.0
HT * CL IN LIQUOR 0.30
NT % MG IN LIQUOR 0.04
HOLD TANK RES. TIME (MINS) 12.0
2816
110675
0700
LS

30.68
29.27
23.13
4.48
6.73

33.0
18.5
39.3
8.2
3.0

15.2
38.7
1.28
5.7

1.589
9.774
0.007
10.690
0.006
6.518
0.004

13.40
0.39
1.25
5.66
52.0
88.6
40.2
0.25
0.44
12.0
2816
111375
0700
LS

26.88
30.71
19.59
5.01
11.75

25.0
30.1
35.4
10.0
3.0

15.4
43.8
1.36
6.7

1.593
9.799
0.004
10.683
0.004
6.508
0.003

16.90
0.32
1.49
6.15
52.0
99.1
39.5
0.17
0.04
12.0
2816
111875
0700
LS

43.03
24.18
22.93
3.78
1.35

40.0
2.0
48.1
13.8
3.3

13.8
41.0
1.29
7.5

1.592
9.790
0.004
10.665
0.004
6.510
0.003

11.60
0.10
1.06
5.25
50.0
63.6
40.2
0.21
0.03
12.0
2816
112875
0700
LS

30.82
28.89
20.98
7.35
5.55

24.0
9.8
54.2
11.0
3.7

14.0
34.0
1.27
4.8

1.590
9.779
0.003
10.665
0.004
6.510
0.002

21.90
0.67
1.22
5.95
51.0
84.0
41.2
0.29
0.05
14.8
2816
120775
0700
LS

30.51
30.57
20.82
4.36
8.69

30.0
19.7
43.9
6.4
2.8

15.7
42.8
1.34
6.3

1.590
9.789
0.002
10.662
0.003
6.495
0.002

14.30
0.26
1.43
6.02
50.0
84.1
40.9
0.24
0.05
14.8
2816
121475
0700
LS

46.02
21.48
21.54
4.38
1.24

27.0
4.8
55.5
12.7
1.6

15.5
41.6
1.31
8.0

1.591
9.794
0.005
10.670
0.006
6.506
0.003

14.00
0.83
0.98
5.49
52.0
64.5
41.1
0.17
0.05
14.8
2816
122575
0700
LS

42.82
24.70
22.56
2.81
2.79

32.0
17.6
44.1
6.8
2.5

14.2
42.0
1.33
4.3

1.593
9.785
0.004
10.661
0.005
6.504
0.003

9.08
1.12
1.14
5.79
50.0
64.0
39.1
0.20
0.05
10.8
2816
010176
0700
LS

44.01
24.65
16.98
5.43
4.46

42.0
8.1
42.4
7.5
3.5

14.9
38.7
1.29
6.3

1.590
9.783
0.002
10.666
0.002
6.519
0.001

20.40
1.11
1.32
5.74
52.0
75.5
40.2
0.31
0.04
10.8
2816
011076
0700
LS

46.16
23.16
19.01
5.59
1.39

47.0
2.3
43.8
6.9
2.7

16.2
39.2
1.28
5.4

0.0
9.786
0.003
10.677
0.004
6.515
0.002

19.00
1.15
1.13
5.48
50.0
56.7
41.0
0.39
0.06
14.8
2816
011676
0730
LS

41.33
24.89
24.28
3.52
1.17

32.5
4.4
5!. 8
11.3
3.6

14.7
39.8
1.26
6.9

1.592
9.816
0.005
10.649
0.005
6.523
0.003

10.40
0.95
1.05
5.49
50.0
71.9
41.1
0.32
0.06
14.8
2816
012376
0700
LS

41.74
25.98
21.58
2.20
4.66

29.2
14.2
47.4
9.2
3.1

14.4
37.0
1.26
6.0

1.591
9.800
0.003
10.674
0.003
6.511
0.002

7.54
0.69
1.27
5.81
50.0
96.0
41.1
0.34
0.05
14.8
2816
020176
0730
LS

45.12
22.05
16.72
8.64
1.37

44.5
1.*
47.3
6.8
3.3

15.7
44.6
1.32
7.7

1.591
9.795
0.004
10.674
0.005
6.515
0.003

29.20
1.12
1.06
5.16
50.0
56.0
41.0
0.24
0.04
10.8

-------
TABLE 1.   TCA SLURRY ANALYSES
RUN NUMBER 58 1-3 A
ANALYSIS POINT 2816
DATE 020876
TIME 0730
ADSORBENT |_S
ON-SITE SOLIDS ANALYSES
ASH 
-------
                                          TABLE 1.  TCA SLURRY ANALYSES
    RUN NUMBER  586-2A   587-2A   587-2A 588-2*   589-2A  601-3*  601-2A  603-2A  604-2A  604-2A  605-2A  606-2A  607-2A
ANALYSIS POINT    2816
2816
2816
2816
                                                2816
                                2816
2816
                                        2816
                                        2816
2816
2816
                                                                               2816
                                                                                                                2816
          DATE   052276   060176   061076  061976  062876  070476  071076  072176  072976  080376  081276  081876  082376
TIKE 0730
ADSORBENT |_S
ON-SITE SOLIDS ANALYSES
ASH (WT %) 46.32
CA (WT 9) 24.50
S02 (WT ») 17.37
S03 (WT »> 2.36
C02 (WT *> 6.16
TVA SOLIDS CHARACTERIZATION
ASH (MT %» ACID INSOLUBLE) 40.0
CAC03 (WT %» BY IR) 16.0
CAS03 X .5 H20 (WT ttt IR) 35.0
CAS04 X 2H20 (WT *. IR) 8.0
SURFACE AREA (SO M/GM) 2.7
TVA SLURRY CHARACTERIZATION
SLURRY SOLIDS % 15.6
~ SETTLED % SOLIDS 42.3
o> SETTLED BULK DENSITY (GM/CC) 1.31
SETTLING RATE (CM/MR) 3.5
TVA CRYSTALL06RAPHIC ANALYSES
SULF1TE REFRACTIVE INDEX 1.589
SULF1TE A AXIS 9.802
STD. ERROR 0.003
SULFITE B AXIS 10.663
STD. ERROR 0.003
SULFITE C AXIS 6.513
STD. ERROR 0.002
SCRUBBER OPERATIONAL PARAMETERS
« SOLID OXIDATION 9.80
SAT. RATIO (RADIAN 50 C.) 0.71
STOIC. RATIO 1.45
SLURRY PH 5.16
SLURRY TEMPERATURE (C) SO.O
MAKE/PASS (MOLES/THOUS GAL) 58.7
LIQ/GAS (GAL/THOUS CFM) 40.0
WT % CL IN LIQUOR 0.39
WT * MG IN LIQUOR 0.82
HOLD TANK RES. TIME (MINS) 3.0
0730
LS

52.77
26.62
8.68
0.01
12.04

45.0
33.0
12.0
10.0
4.1

10.5
25.8
1.17
2.5

1.589
9.803
0.004
10.649
0.004
6.484
0.002

0.10
0.16
3.49
5.94
50.0
86.0
40.0
0.03
0.75
3.0
0730
LS

40.82
26.76
10.47
10.69
5.99

33.0
3.0
56.0
8.0
5.7

10.1
34.0
1.28
5.6

1.587
9.793
0.002
10.677
0.003
6.497
0.002

44.90
1.43
1.60
4.98
51.0
90.9
41.0
0.20
1.02
4.1
0730
LS

39.27
29.03
9.91
5.71
12.55

30.0
36.0
20.0
14.0
4.8

15.2
42.8
1.36
3.0

1.587
9.785
0.003
10.668
0.004
6.529
0.002

31.50
1.15
2.28
5.43
50.0
55.0
60.1
0.51
1.13
4.1
0730
LS

36.93
27.04
18.03
6.82
5.67

30.0
11.0
48.0
11.0
5.6

15.1
32.0
1.26
2.4

1.588
9.803
0.002
10.667
0.002
6.513
0.001

23.20
1.06
1.31
5.32
56.0
97.6
40.7
0.14
1.11
4.1
0730
LIME

38.82
26.92
22.99
5.76
0.57

30.0
0.0
60.0
10.0
6.1

9.5
43.0
1.30
42.6

1.574
9.782
0.003
10.675
0.003
6.511
0.002

16.70
0.79
1.11
6.04
50.0
72.6
41.6
0.11
0.15
4.1
0730
LIME

50.47
20.73
19.92
3.93
0.56

35.0
5.0
52.0
8.0
5.8

9.5
50.8
1.22
50.0

1.574
9.786
0.002
10.679
0.002
6.507
0.001

13.60
0.93
1.02
7.07
52.0
63.2
45.5
0.16
0.27
4.1
0730
LIME

55.49
18.63
17.73
3.69
0.49

45.0
0.0
40.0
15.0
5.2

9.2
43.0
1.35
3.4

1.586
9.783
0.004
10.691
0.004
6.501
0.003

14.30
0.83
1.02
6.64
53.0
57.4
40.9
0.29
0.30
4.1
0730
LIME

46.14
23.12
18.53
7.13
0.05

30.0
0.0
59.0
11.0
6.5

8.5
46.9
1.34
32.2

1.585
9.789
0.003
10.671
0.003
6.514
0.002

23.50
0.83
1.08
6.82
50.0
120.5
31.6
0.35
0.34
4.1
0730
LIME

33.19
25.15
18.88
13.64
0.27

40.0
0.0
50.0
10.0
6.8

10.1
48.6
1.27
33.2

1.580
9.786
0.002
10.688
0.002
6.506
0.001

36.60
0.94
0.96
6.94
51.0
104.0
30.8
0.30
0.30
4.1
0730
LIME

28.24
29.75
28.23
6.64
0.46

25.0
4.0
61.0
10.0
6.3

7.7
39.5
1.30
30.9

1.5B7
9.789
0.002
10.656
0.003
6.512
0.002

15.80
0.33
1.01
0.0
50.0
10.3
60.2
0.26
0.33
4.1
0730
LIME

53.08
20.33
18.36
3.94
0.43

45.0
1.0
45.0
9.0
8.1

8.5
44.9
1.32
42.6

1.590
9.786
0.003
10.683
0.003
6.506
0.002

14.60
0.86
1.07
7.93
52.0
106.3
30.9
0.27
0.32
0.0
0730
LIME

45.10
23.60
18.08
7.44
0.65

35.0
3.0
46.0
16.0
7.1

9.1
47.1
1.33
32.6

1.586
9.774
0.002
10.694
0.002
6.511
0.001

24,70
0,93
1.12
7.90
54.0
95.3
30.7
0.25
0.51
0.0

-------
TABLE 1.  TCA SLURRY ANALYSES
RUN NUMBER 608-2A
ANALYSIS POINT 2616
DATE 090476
TIME 0730
AOSORBENT LIME
ON-SITE SOLIDS ANALYSES
ASH (WT *> 34.47
CA (WT «) 26.97
S02 (WT «> 24.61
503 (WT *> 6.53
C02 (WT %> 1.15
TVA SOLIDS CHARACTERISATION
ASH (WT «. ACID INSOLUBLE) 35.0
CAC03 (WT %. BY IR) 2.0
CAS03 X .5 H20 (WT %. IR) 54.0
CAS04 X 2H20 (WT *t IR) 10.0
SURFACE AREA (SO M/GM) 7.8
TVA SLURRY CHARACTERIZATION
SLURRY SOLIDS % 16.3
SETTLED * SOLIDS 47.6
SETTLED BULK DENSITY (GM/CC) 1.38
SETTLING RATE < CM/MR > 37.2
TVA CRYSTALLOGRAPHIC ANALYSES
SULFITE REFRACTIVE INDEX 1.581
SULFITE A AXIS 9.782
STO. ERROR 0.002
SULFITE 8 AXIS 10.675
STD. ERROR 0.002
SULFITE C AXIS 6.512
STO. ERROR 0.001
SCRUBBER OPERATIONAL PARAMETERS
% SOLID OXIDATION 17.50
SAT. RATIO (RADIAN 50 C.) 1.11
STOIC. RATIO 1.03
SLURRY PH 7.85
SLURRY TEMPERATURE (C) 54.0
MAKE/PASS (MOLES/THOUS GAL) 124.8
LIO/GAS (GAL/TMOUS CFM) 30.5
WT * CL IN LIQUOR 0.25
WT % MG IN LIQUOR 0.50
HOLD TANK RES. TIME (MINS) o.o
608-2A
2816
090976
0730
LIME

34.17
27.42
25.69
5.38
1.43

30.0
3.0
56.0
11.0
7.2

16.2
45.0
1.37
8.6

1.585
9.794
0.004
10.664
0.004
6.486
0.003

14.30
0.08
1.04
7.96
50.0
127.7
30.4
0.28
0.52
0.0
609-2A
2816
091576
0730
LIME

47.22
24.09
22.57
2.08
0.75

45.0
0.0
45.0
10.0
4.6

10.9
53.0
1.33
26.9

1.587
9.800
0.003
10.674
0.003
6.503
0.002

6.87
0.18
1.14
6.99
53.0
132.9
30.8
0.36
0.38
0.0
609-2A
2816
092276
0730
LIME

34.87
26.79
24.81
6.81
0.41

45.0
1.0
46.0
8.0
3.9

7.9
45.2
1.38
52.6

1.582
9.786
0.002
10.652
0.002
6.511
0.001

18.00
0.55
1.01
6.84
53.0
103.1
31.2
0.34
0.33
5.4
6 10-2 A
2816
092976
0730
LIME

40.10
26.79
27.03
1.48
0.76

25.0
3.0
62.0
10.0
5.2

7.8
41.7
1.36
52.1

1.585
9.793
0.003
10.666
0.003
6.501
0.002

4.20
0.12
1.08
7.68
53.0
117.6
31.0
0.30
0.33
5.4
610-2A
2816
100676
0730
LIME

50.89
22.48
22.44
0.88
0.47

35.0
2.0
49.0
14.0
4.0

7.7
43.4
1.33
67.2

1.582
9.768
0.002
10.665
0.002
6.514
0.002

3.00
0.82
1.10
7.95
50.0
103.4
30.6
0.41
0.35
4.1
611-2A
2816
101076
0730
LIME

38.38
24.95
16.64
12.19
0.60

35.0
3.0
41.0
22.0
7.5

9.0
40.2
1.33
39.2

1.583
9.796
0.003
10.677
0.004
6.505
0.002

36.90
0.95
1.07
8.08
49.0
102.5
30.8
0.55
0.43
4.1
613-2A
2816
102076
0730
LIME

42.50
23.13
15.56
11.24
0.77

40.0
0.0
31.0
29.0
8.2

9.2
42.0
1.33
34.8

1.581
9.779
0.004
10.676
0.004
6.520
0.003

36.60
0.86
1.07
6.74
54.0
87.8
41.5
0.56
0.44
3.0
614-2A
2816
102776
0730
LIME

39.34
27.62
25.41
2.89
0.83

30.0
0.0
58.0
12.0
5.6

7.9
38.7
1.29
36.6

1.587
9.779
0.003
10.675
0.003
6.508
0.002

8.30
0.80
1.14
8.08
48.0
123.3
31.0
0.44
0.35
16.0
616-2A
2816
110676
0730
LIME

51.44
22.32
20.45
1.50
1.43

38.0
6.0
43.0
14.0
5.9

9.1
38.7
1.31
33.8

1.582
9.757
0.002
10.670
0.003
6.507
0.002

5.50
0.89
1.17
8.32
53.0
74.9
40.8
0.25
0.02
12.0
616-2A
2816
111176
0730
LIME

42.90
23.20
19.45
7.59
0.89

40.0
2.0
48.0
10.0
6.8

7.8
46.4
1.35
67.8

1.585
9.781
0.002
10.660
0.002
6.514
0.001

23.70
1.29
1.03
5.74
51.0
76.8
40.8
0.47
0.03
12.0
617-2A
2816
111776
0730
LIME

40.69
25.27
22.44
5.22
1.26

25.0
s.o
59.0
11.0
4.6

20.2
57.1
1.36
9.4

0»0>
9.773
0.002
10.653
0.002
6.514
0.001

15.60
1.06
1.08
8.00
50.0
80.9
40.6
0.39
0.05
12.0
701-2A
2816
112676
0730
LS

5.19
43.10
36.55
5.06
3.91

5.0
18.0
63.0
14. 0
*.o

7.6
24.9
1.19
5.4

0.0
9.793
0.002
10.663
0.002
6.509
0.001

9.90
0.81
1.21
5.64
50.0
72.3
40.2
0.35
0.02
4.1

-------
                                                  TABLE 1.   TCA SLURRY ANALYSES
CO
RUN NUMBER TO 1-2 A
ANALYSIS POINT 2816
DATE 113076
TIME 0730
ADSORBENT LS
ON-SITE SOLIDS ANALYSES
ASM (WT *> 3.12
CA (WT ft) 41.30
S02 (WT X) 27.87
S03 (WT »> 14.13
C02 (WT *) 4.23
TVA SOLIDS CHARACTERIZATION
ASH (WT ». ACID INSOLUBLE) 5.0
CACO3 (WT Ct BY IR) 16.0
CAS03 X .5 H20 (WT *t IR) 60.0
CAS04 X 2H20 (WT %» IR) 19.0
SURFACE AREA (SO M/GM) 5.2
TVA SLURRY CHARACTERIZATION
SLURRY SOLIDS * 8.3
SETTLED » SOLIDS 24.4
SETTLED BULK DENSITY (6M/CC) 1.18
SETTLING RATE (CM/HR) 4.8
TVA CRYSTALL06RAPHIC ANALYSES
SULFITE REFRACTIVE INDEX 0.0
SULFITE A AXIS 9.781
STD. ERROR 0.002
SULFITE 8 AXIS 10.664
STD. ERROR 0.002
SULFITE C AXIS 6.514
STO. ERROR 0.001
SCRUBBER OPERATIONAL PARAMETERS
% SOLID OXIDATION 20.00
SAT. RATIO (RADIAN 50 C.) 1.07
STOIC. RATIO 1.20
SLURRY PH 5.57
SLURRY TEMPERATURE (C) 53.0
MAKE/PASS (MOLES/THOUS GAL) 64.7
LIO/GAS (GAL/THOUS CFM) 40.6
WT % CL IN LIOUOR 0.27
WT « MG IN LIQUOR 0.04
HOLD TANK RES. TIME (MINS) 4.1
702-2A
2816
120976
0730
LS

10.01
40.37
41.21
0.25
2.85

0.0
14.0
71.0
14.0
2.1

15.1
41.4
1.31
5.4

0.0
9.794
0.002
10.670
0.002
6.493
0.001

0.40
0.17
1.11
5.70
50.0
77.1
40.7
0.37
0.08
0.0
703-2A
2816
121676
0730
LS

12.04
38.42
33.29
5.93
3.57

0.0
10.0
80.0
11.0
2.2

7.7
33.1
1.23
13.8

0.0
9.791
0.002
10.655
0.002
6.502
0.001

12.40
0.21
1.15
5.66
49.0
88.4
41.0
0.36
0.05
0.0
704-2A
2816
122376
0730
LS

7.32
41.84
41.62
0.81
2.97

0.0
13.0
73.0
14.0
2.4

8.2
33.7
1.24
17.1

0.0
9.794
0.003
10.669
0.003
6.496
0.002

1.50
0.31
1.13
5.77
50.0
61.3
40.4
0.36
0.06
0.0
704-2A
2816
123076
0730
LS

3.48
43.81
36.55
6.66
2.86

0.0
10.0
77.0
13.0
2.4

8.0
37.5
1.22
10.9

0.0
9.773
0.004
10.671
0.004
6.502
0.002

11.80
0.47
1.20
5.71
52.0
86.6
40.9
0.31
0.06
12.0
705-2A
2816
010777
0730
LS

13.04
38.81
32.45
5.27
4.29

3.0
21.0
63.0
13.0
2.3

15.9
38.9
1.27
5.5

0.0
9.791
0.002
10.682
0.003
6.507
0.002

11.50
1.44
1.20
5.91
50.0
76.9
40.8
0.24
0.06
12.0
705-2A
2816
011277
0730
LS

9.36
40.88
38.00
2.67
3.41

0.0
11.0
82.0
6.0
1.8

15.2
41.6
1.30
5.6

0.0
9.788
0.002
10.652
0.002
6.500
0.001

5.30
0.32
1.16
5.86
50.0
80.7
41.0
0.35
0.06
12.0
706-2A
2816
012277
0730
LS

0.0
42.54
30.27
12.76
6.57

0.0
16.0
68.0
16.0
2.9

15.2
39.0
1.30
4.0

0.0
9.792
0.002
10.658
0.002
6.512
0.001

25.20
1.01
1.19
5.70
47.0
78.8
41.0
0.32
0.06
12.0
706-1A
2816
012877
0730
LS

16.66
35.44
33.22
4.50
3.52

5.0
7.0
80.0
8.0
2.6

14.5
37.6
1.31
4.5

0.0
9.778
0.002
10.668
0.002
6.513
0.001

9.70
0.16
1.09
5.50
53.0
72.7
40.7
0.27
0.06
12.0
706-2A
2816
020377
0730
LS

4.18
39.49
33.97
8.93
4.46

2.0
7.0
75.0
16.0
2.9

15.4
35.8
1.26
4.6

0.0
9.783
0.003
10.659
0.0.03
6.519
0.002

10.80
1.33
1.18
5.41
48.0
64.1
41.3
0.43
0.07
12.0
TFG-2C
2816
021177
0715
LS

38.90
26.96
21.71
3.97
3.96

35.0
15.0
38.0
11.0
3.7

15.3
40.7
1.33
6.0

0.0
9.784
0.002
10.664
0.002
6.517
0.001

12.70
0.96
1.23
5.71
50.0
95.8
41.1
0.46
0.07
12.0
TFG-2D
2816
021877
0715
LS

31.47
31.08
24.84
4.60
3.33

35.0
9.0
45.0
10.0
3.5

13.9
40.2
1.30
7.0

0.0
9.794
0.002
10.663
0.002
6.508
0.001

12.90
0.79
1.24
5.91
49.0
73.3
61.0
0.02
0.05
12.0
TFG-2F
2816
022477
0715
LS

34.00
28.60
20.99
7.76
2.86

40.0
5.0
48.0
8.0
5.0

15.5
36.3
1.28
*.o

0.0
9.799
0.003
10.660
0.003
6.517
0.002

22.80
0.69
1.20
5.66
53.0
78.6
40.8
0.33
0.05
12.0

-------
                                                  TABLE 1.   TCA SLURRY ANALYSES
vo
RUN NUMBER TFG-2F
ANALYSIS POINT 2816
DATE 022877
TIME 0715
ADSORBENT LS
ON-SITE SOLIDS ANALYSES
ASH (WT ft) 32.74
CA (WT ft) 29.07
S02 (WT ft) 23.98
S03 (WT ft) 4.81
C02 (WT ft) 4.06
TVA SOLIDS CHARACTERIZATION
ASM (WT ft. ACID INSOLUBLE) 35.0
CAC03 (WT ». BY IR) 9.0
CAS03 X .5 H20 (WT ft* IR) 46.0
CA504 X 2H20 (WT «, IR) 10.0
SURFACE AREA (SO M/GM) 4.7
TVA SLURRY CHARACTERIZATION
SLURRY SOLIDS ft 14.3
SETTLED « SOLIDS 35.9
SETTLED BULK DENSITY (9M/CC) 1.27
SETTLING RATE (CM/HR) 5.5
TVA CRYSTALL06RAPHIC ANALYSES
SULFITE REFRACTIVE INDEX 0.0
SULFITE A AX.IS 9.793
STO. ERROR 0.004
SULFITE 8 AXIS 10.672
STD. ERROR 0.005
SULFITE C AXIS 6.511
STD. ERROR 0.003
SCRUBBER OPERATIONAL PARAMETERS
ft SOLID OXIDATION 13.80
SAT. RATIO (RADIAN 50 C.) 0.84
STOIC. RATIO 1.19
SLURRY PH 5.57
SLURRY TEMPERATURE (C) 50.0
MAKE/PASS (MOLES/THOUS GAL) 74.3
LIO/OAS (GAL/THOUS CFM) 40.8
WT « CL IN LIQUOR 0.32
WT ft MG IN LIQUOR 0.06
HOLD TANK RES. TIME (MINS) 12.0
707-2A
2816
030877
0715
LS

39.11
26.86
19.54
5.71
3.97

35.0
12.0
42.0
11.0
4.4

16.3
41.6
1.30
6.4

0.0
9.796
0.003
10.662
0.003
6.520
0.002

18.90
1.47
1.27
5.54
50.0
64.6
41.0
0.41
0.05
4.1
709-2A
2816
031677
0715
LS

42.30
25.00
17.30
5.81
4.75

35.0
16.0
38.0
11.0
2.7

14.9
44.5
1.39
10.5

0.0
9. SOB
0.002
10.667
0.002
6.516
0.002

19.30
1.11
1.33
5.41
50.0
59.8
41.0
0.15
0.03
4.1
710-2A
2816
032277
0715
LS

44.41
24.74
19.54
3.86
3.41

35.0
5.0
50.0
10.0
3.8

15.5
41.6
1.32
6.9

0.0
9.781
0.002
10.657
0.002
6.521
0.001

13.60
1.19
1.24
5.77
53.0
58.5
40.9
0.19
0.04
10.0
711-2A
2816
032877
0715
LS

39.11
28.35
25.25
1.S9
2.3«

30.0
13.0
45.0
12.0
3.1

14.2
40.5
1.33
8.2

0.0
9.782
0.002
10.659
0.002
6.512
0.001

4.80
0.63
1.22
5.62
51.0
68.3
41.4
0.20
0.05
12.0

-------
                                             TABLE 2.  VENTURI/SPRAY  TOWER SLURRY ANALYSES
              RUN NUMBER  623-1A  633-1A  624-1A  62*-1A  627-1A  638-1A  628-18  628-1B   628-18  701-1*  703-1*  703-1A  704-1*
ANALYSIS POINT
          DATE
                           1816
1816
1816
                                                   1816
1816
1816
1816
                                               1816
1816
1816
1816
                          031375  031*75  040375  041175  080875  091475  093175  090875   100575   161Z75  103175
 1816    1816
102875  110675
TIME 1300
ADSORBENT LIME
ON-SITE SOLIDS ANALYSES
ASH fWT ft) 0.0
CA (WT ft) 0.0
S02 (WT ft) 0.0
SO3 (WT ft) 0.0
C02 (WT ft) 0.0
TVA SOLIDS CHARACTERIZATION
ASH (WT ft* ACID INSOLUBLE) 33.0
CAC03 (WT ft* BY IR) 3.3
CASO3 X .5 H20 (WT ft* IR) 59.0
CASO4 X 2H20 (WT ft. IR) 4.5
SURFACE AREA (SO M/GM) 7.0
TVA SLURRY CHARACTERIZATION
SLURRY SOL I OS ft 8.8
SETTLED ft SOLIDS 38.1
SETTLED BULK DENSITY (OM/CC) 1.32
SETTLING RATE (CM/MR) 12.4
TVA CRYSTALLOGRAPHIC ANALYSES
SULFITE REFRACTIVE INDEX 1.592
SULFITE A AXIS 9.743
STO. ERROR 0.010
SULFITE B AXIS 10.630
STO. ERROR 0.006
SULFITE C AXIS 6.502
STO.. ERROR 0.005
SCRUBBER OPERATIONAL PARAMETERS
ft SOLID OXIDATION 0.0
SAT. RATIO (RADIAN 50 C.) 0.98
STOIC. RATIO 0.0
SLURRY PH 7.90
SLURRY TEMPERATURE (C) 51.0
MAKE/PASS (MOLES/THOUS GAL) 0.0
LIO/6AS (GAL/THOUS CFM) 0.0
WT ft CL IN LIQUOR 0.33
WT ft MG IN LIQUOR 0.02
HOLD TANK RES. TIME (MINS) 17.0
1300
LIME

37.71
26.66
22.08
6.06
2.08

33.0
5.6
53.0
9.0
5.9

7.3
32. 2
1.22
11.5

1.581
9.750
0.012
10.632
0.006
6.495
0.005

18.00
0.71
1.13
7.70
50.0
0.0
0.0
0.31
0.02
17.0
700
LIME

38.46
2S.99
23.11
5.04
2.06

69.0
1.4
27.0
2.0
4.6

11.6
39.1
1.35
8.7

1.584
9.759
0.019
10.619
0.011
6.493
0.010

14.80
0.0
1.09
8.80
50.0
0.0
0.0
0.0
0.0
17.0
1145
LIME

0.0
0.0
0.0
0.0
0.0

45.0
5.0
45.0
7.2
3.0

7.9
46.4
1.45
13.9

1.590
9.799
0.035
10.665
0.019
6.498
0.018

0.0
1.17
0.0
0.0
0.0
0.0
0.0
0.43
0.02
17.0
1220
LIME

45.30
24.34
17.24
5.14
3.76

40.0
10.2
38.4
11.4
8.1

15.6
34.0
1.24
2.4

1.593
9.769
0.003
10.729
0.004
6.510
0.004

19.30
0.0
0.0
0.0
0.0
0.0
0.0
0.0
0.0
20.0
0700
LIME

39.58
24.81
20.76
6.92
1.97

35.0
8.3
43.3
13.4
4.1

8.7
44.9
1.30
38.4

1.590
9.776
0.006
10.636
0.006
6.531
0.005

21.00
1.03
1.08
7.95
52.0
40.6
90.4
0.31
0.03
12.0
0700
LIME

39.23
2S.32
22.08
5.88
1.88

40.0
6.5
47.6
5.8
4.3

9.4
39.6
1.28
35.6

1.590
9.775
0.006
10.673
0.006
6.521
0.005

17.60
0.84
1.08
8.25
53.0
41.8
97.4
0.33
0.03
12.0
0700
LIME

39.62
24.63
21.98
4.11
4.19

41.5
3.9
44.8
9.8
5.1

25.7
42.1
1.31
2.1

1.589
9.764
0.010
10.678
0.010
6.514
0.007

13.00
0.69
1.11
8.10
50.0
49.4
82.9
0.37
0.02
12.0
0700
LIME

39.22
24.81
23.19
5.15
1.90

33.0
3.7
53.1
10.2
4.1

9.5
44.5
1.26
20.5

1.588
9.778
0.003
10.667
0.003
6.518
0.003

15.10
0.73
1.04
7.95
52.0
53.6
68.8
0.44
0.03
12.0
0700
LS

27.70
32. OS
19.86
7.19
7.54

27.0
21.1
44.8
7.1
3.4

18.4
37.0
1.27
2.5

1.589
9.798
0.005
10.690
O.OOS
6.506
0.004

22.40
0.23
1.43
5.85
54.0
50.1
69.2
0.49
0.05
20.0
0700
LS

44.62
23.00
21.60
4.10
1.76

45.0
2.8
45.0
7.2
2.2

10.2
44.7
1.29
9.6

1.590
9.769
0.006
10.690
0.005
6.519
0.004

13.20
0.0
1.06
5.25
50.0
0.0
63.7
0.0
0.0
20.0
0900
LS

43.15
24.34
22.07
3.44
2.47

45.0
6.0
41.0
8.0
1.8

12.8
45.5
1.36
7.8

1.590
9.799
0.006
10.680
0.006
6.527
0.005

11.10
0.71
1.13
5.31
51.0
42.2
63.6
0.67
0.07
20.0
0700
LS

30.27
33.49
20.95
2.64
9.31

27.0
30.9
34.8
7.3
2.5

16.4

1.34
4.3

1.591
9.795
0.006
10.683
0.006
6.511
0.005

9.20
0.12
1.66
5.84
52.0
70.0
64.3
0.5*
0.11
20.0
LS = Limestone

-------
TABLE 2.  VENTURI/SPRAY TOWER SLURRY ANALYSES
RUN NUMBER 705-1 A
ANALYSIS POIVT 1816
DATE 111376
TIME 0700
ADSORBENT LS
ON-SITE SOLIDS ANALYSES
ASH (WT *) 34.81
CA (WT «) 37.43
S02 (WT *) 23.80
S03 (WT *) 1.59
C02 (WT «> 7.47
TVA SOLIDS CHARACTERIZATION
ASH (WT *. ACID INSOLUBLE) 35.0
CAC03 (WT «, BY IR) 16.4
CAS03 X .5 H20 (WT %. IR) 40.1
CAS04 X 2H20 (WT %» IR) 8.4
SURFACE ARC A (SQ M/GM) 1.8
TVA SLURRY CHARACTERIZATION
SLURRY SOLIDS « 14.5
SETTLED % SOLIDS 50.3
SETTLED BULK DENSITY (GM/CC) 1.33
SETTLING RATE (CM/HR) 9.0
TVA CRYSTALL06RAPHIC ANALYSES
SULFITE REFRACTIVE INDEX 1.591
SULFITE A AXIS 9.781
STD. ERROR 0.005
SULFITE B AXIS 10.679
STD. ERROR 0.004
SULFITE C AXIS 6.509
STD. ERROR 0.003
SCRUBBER OPERATIONAL PARAMETERS
% SOLID OXIDATION 5.10
SAT. RATIO (RADIAN 50 C.) 0.25
STOIC. RATIO 1.25
SLURRY PH 6.00
SLURRY TEMPERATURE (C<> 52.0
MAKE/PASS (MOLES/THOUS GAL) 61.1
LIO/GAS (GAL/THOUS CFM) 67.0
WT * CL IN LIOUOR 0.34
WT % MG IN LIQUOR 0.06
HOLD TANK RES. TIME (MINS) 20.0
706-1A
1816
111975
0700
LS

42.00
23.99
23.25
4.12
1.47

40.0
2.0
48.1
10.0
2.2

12.6
40.6
1.40
8.5

1.592
9.790
0.010
10.691
0.006
6.534
0.005

12.40
1.11
1.03
5.25
50.0
47.1
63.9
0.37
0.07
12.0
708-1 A
1816
112775
0700
LS

31.63
29.27
20.17
6.31
6.84

27.0
11.1
54.1
7.8
2.2

14.4
44.6
1.34
4.5

1.590
9.790
0.003
10.657
0.004
6.503
0.002

21.30
0.57
1.30
s.es
51.0
47.5
63.9
0.45
0.09
12.0
709-1A
1816
120775
0700
LS

37.84
26.88
20.56
4.66
5.12

30.0
13.4
47.5
9.1
2.5

15.2
43.5
1.31
3.6

1.592
9.785
0.002
10.673
0.002
6.505
0.001

15.30
0.57
1.26
5.71
51.0
53.0
63.9
0.42
0.09
12.0
T10-IA
1816
121475
0700
LS

34.35
28.54
20.43
3.72
8.09

32.0
22.4
39.5
6.1
2.3

16.4
43.5
1.32
3.9

1.595
9.797
0.003
10.660
0.003
6.492
0.002

12.73
0.15
1.39
6.03
55.0
63.3
63.1
0.37
O.OB
12.0
710-1A
1016
122275
0700
LS

38.27
26.71
24.50
1.82
4.31

42.0
12.4
41.5
9.1
1.9

16.3
43.2
1.34
4.6

1.594
9.788
0.002
10.667
0.003
6.501
0.002

5.62
0.23
1.18
5.83
52.0
63.9
64.1
0.37
0.09
12.0
711-18
1816
010176
0700
LS

38.87
27.41
17.94
4.43
7.04

37.0
15.2
39.1
8.7
3.1

16.0
40.8
1.29
3.4

1.591
9.800
0.004
10.665
0.004
6.515
0.002

16.50
0.90
1.46
5.57
52.0
58.3
63.7
0.56
0.07
6.0
713-1A
1816
010976
0700
LS

49.98
22.47
17.87
4.08
1.93

43.0
6.8
41.9
8.3
2.9

15.0
41.8
1.30
4.8

1.590
9.791
0.002
10.673
0.002
6.519
0.001

15.40
1.17
1.21
5.14
48.0
49.6
64.2
0.55
O.OB
6.0

1816
012276
0700
LS

34.98
28.28
22.95
3.42
5.56

35.5
11.9
4*. 7
7.9
3.1

17.2
41.6
1.30
2.8

1.591
9.795
0.003
10.660
0.004
6.517
0.002

10.60
1.11
1.26
5.50
50.0
52.5
65.6
0.44
0.46
6.0
717-1A
1816
013176
0730
LS

36.41
27.46
22.49
4.79
3.74

39.0
5.6
50.3
5.1
2.3

15.9
42.7
1.30
3.6

1.591
9.806
0.003
10.665
0.003
6.511
0.002

14.50
0.64
1.19
5.53
50.0
53.8
64.1
0.34
0.43
6.0
FACT.
1816
021576
0730
LIME

33.06
28.70
22.62
7.64
1.98

34.5
4.7
53.8
7.0
5.2

17.2
50.9
1.29
6.3

1.590
9.786
0.003
10.653
0.003
6.450
0.002

21.30
0.54
1.14
7.93
50.0
41.0
85.0
0.49
0.05
12.0
FACT.
1816
022176
0730
LIME

55.91
19.16
13.71
6.04
1.16

61.0
5.3
27.7
6.0
5.0

16.6
55.6
1.37
8.7

1.586
9.774
0.004
10.652
0.004
6.501
0.002

26.10
1.22
1.18
8.13
51.0
33.2
43.6
0.88
0.04
0.0
FACT.
1816
030276
0730
LIME

56.99
20.36
16.45
2.56
1.17

45.0
3.0
40.0
13.0
5.0

16.1
46.9
1.35
5.8

1.585
9.773
0.004
10.650
0.004
6.511
0.002

11.10
1.19
1.23
8.18
50.0
68.6
5.3
1.22
0.06
6.0

-------
TABLE 2.  VENTURI/SPRAY TOWER SLURRY ANALYSES
RUN NUMBER FACT.
ANALYSIS POINT 1816
DATE 030676
TIME 0730
ADSORBENT LS
ON-SITE SOLIDS ANALYSES
ASH (WT ») 41.73
CA (WT «) 27.5e
SO? (WT *) 19.19
S03 (WT %) 2.95
C02 (WT %) 5.37
TVA SOLIDS CHARACTERIZATION
ASH (WT «• ACID INSOLUBLE) 33.0
CAC03 (WT ft. BY IPO 13.0
CAS03 X .5 H20 (WT %. IR) 43.0
CAS04 X 2H20 (WT *. IR> 11.0
SURFACE AREA (SO M/GM) 5.3
TVA SLURRY CHARACTERIZATION
SLW»RY SOLIDS % 15.5
SETTLED » SOLIDS 44.4
SETTLED BULK DENSITY (GM/CC) 1.35
SETTLING RATE 
-------
TABLE 2.  VENTURI/SPRAY TOWER SLURRY ANALYSES
RUN NUMBER 634-1 A
ANALYSIS POINT 1816
DATE 062776
TIME 0730
ADSORBENT LIME
ON-SITE SOLIDS ANALYSES
ASH (WT *> 2.44
CA (WT %) 40.97
SO2 (WT *) 34.54
S03 (WT «) 10.23
C02 (WT ») 2.82
TVA SOLIDS CHARACTERIZATION
ASH (WT %« ACID INSOLUBLE) 1.0
CACO3 (WT %» BY IR) 8.0
CAS03 X .5 H20 (WT %, IR) 80.0
CAS04 X 2H2O (WT %, IR) 12.0
SURFACE AREA (SQ M/GM) 7.1
TVA SLURRY CHARACTERIZATION
SLURRY SOLIDS * 4.5
SETTLED * SOLIDS 40.6
SETTLED BULK DENSITY (GM/CC) 1.21
SETTLING RATE (CM/HR) 90.0
TVA C«YST ALLOGRAPH 1C ANALYSES
SULFITE REFRACTIVE INDEX 1.595
SULFITE A AXIS 9.764
STO. ERROR 0.002
SULFITE B AXIS 10.656
STD. ERROR 0.002
SULFITE C AXIS 6.508
STO. ERROR 0.001
SCRUBBER OPERATIONAL PARAMETERS
ft SOLID OXIDATION 19.10
SAT. RATIO (RADIAN 50 C.) 1.19
STOIC. RATIO 1.09
SLURRY PH 7.94
SLURRY TEMPERATURE (CJ 53.0
MAKE/PASS (MOLES/THOUS GAL) 39.8
LIQ/GAS (GAL/THOOS CFM) 64.0
MT % CL IN LIQUOR 0.37
MT * MG IN LIQUOR 0.06
HOLD TANK RES. TIME (MINS) 12.0
718-1A
1816
070376
0800
LIME

4.60
38.71
25.00
19.04
1.47

1.0
6.0
66.0
28.0
4.4

4.5
37.2
1.31
67.7

1.593
9.766
0.002
10.670
0.002
6.502
0.001

37.80
1.09
1.09
5.33
50.0
22.6
111.0
0.44
0.04
12.0
718-1A
1816
071176
0730
LS

0.0
47.23
31.12
17.05
5.50

1.0
14.0
66.0
20.0
4.6

9.2
30.9
1.22
4.6

1.586
9.792
0.003
10.675
0.003
6.506
0.002

30.40
1.16
1.20
5.87
53.0
38.7
63.0
0.48
0.06
12.0
635-1 A
1816
072076
0730
LIME

10.90
39.53
34.69
4.76
3.82

1.0
10.0
83.0
7.0
10.4

9.4
36.0
1.19
8.4

1.580
9.767
0.002
10.633
0.002
6.510
•0.001

9.80
0.44
1.17
8.65
52.0
37.6
63.1
0.42
0.05
12.0
635-1A
1816
072676
0730
LIME

0.0
42.41
28.15
19.35
2.94

1.0
9.0
78.0
13.0
7.4

9.0
36.6
1.31
10.9

1.582
9.77*
0.002
10.645
0.003
6.504
0.002

35.40
1.00
1.11
7.95
53.0
44.1
63.5
0.45
0.07
12.0
636-1A
1816
080176
0730
LIME

2.23
42.72
35.47
8.84
2.80

1.0
12.0
75.0
13.0
10.3

10.3
42.4
1.21
8.7

1.585
9.736
0.002
10.663
0.002
6.511
0.001

16.60
0.99
1.14
7.87
50.0
36.2
89.3
0.44
0.07
12.0
637-1A
1816
081176
0730
LIME

0.41
44.80
37.39
8.21
1.87

1.0
7.0
83.0
11.0
6.3

8.6
39.6
1.25
28.2

1.584
9.773
0.003
10.653
0.003
6.513
0.002

14.90
0.97
1.08
7.96
50.0
37.7
74.3
0.36
0.06
12.0
638-1A
1816
081776
0730
LIME

0.0
40.36
36.54
10.91
2.44

1.0
7.0
80.0
13.0
5.6

5.0
40.7
1.30
87.0

1.600
9.772
0.003
10.646
0.0*3
6.515
0.002

19.20
1.18
1.01
7.91
52.0
42.8
63.7
0.29
0.06
3.0
639-1A
1816
082576
0730
LIME

0.0
41.02
41.98
7.05
2.10

1.0
5.0
88.0
7.0
8.9

5.5
37.8
1.22
46.1

1.590
9.797
0.002
10.647
0.003
6.495
0.002

11.80
0.05
0.98
6.99
54.0
44.4
63.7
0.35
0.28
3.0
640-1*
1816
090576
0730
LIME

3.12
41.69
38.62
7.46
1.14

1.0
4.0
82.0
14.0
5.4

10.8
53.9
1.31
31.3

1.583
9.791
0.003
10.672
0.003
6.513
0.002

13.30
0.75
1.06
6.87
54.0
51.4
64.3
0.34
0.30
3.0
641-1*
1816
091076
0730
LIME

0.0
45.37
39.42
12.47
1.52

1.0
2.0
86.0
12.0
5.6

8.3
41.9
1.25
34.9

1.580
9.781
0.003
10.662
0.003
6.511
0.002

20.20
0.36
1.04
7.04
54.0
48.6
45.1
0.55
0.40
3.0
642-1 A
1816
091676
0730
LIME

14.17
36.14
36.73
5.40
0.32

1.0
1.0
88.0
12.0
5.0

8.2
40.8
1.30
22.3

1.585
9.788
0.003
10.659
0.003
6.514
0.002

10.50
0.61
1.01
6.55
53.0
61.4
34.9
0.54
0.36
3.0
642-1*
1816
092376
0730
LIME

1.97
41.40
37.82
9.37
0.64

1.0
2.0
84.0
14.0
4.6

8.1
40.2
1.29
32.2

1.562
9.789
0.002
10.666
0.002
6.511
0.001

16.50
0.84
1.04
6.94
52.0
60.2
34.8
0.64
0.44
3.0

-------
                                   TABLE 2.  VENTURI/SPRAY TOWER SLURRY ANALYSES
    RUN NUMBER   643-U  6*3-1* VFG-001  VFO-1B  VFG-1B  VFG-1D  VF6-1F   VFS-lf   VF6-1I  VFO-1P  801-1*  801-1*  802-U
ANALYSIS POINT    1816
1816
1816
1816
                        1816
1816
1816
1816
1816
1816
1816
                                                                                                       1816
                                                                               1816
          DATE   092876   100476  101176  102176  102876  110576  111276  111676   112576   120176  010877  011177  012777
TJME 0730
ADSORBENT LIME
OW-SITE SOLIDS ANALYSES
ASH (WT ») 0.0
CA (WT *) 43.71
S02 (WT *) 39.09
SOS (WT *> 13.19
C02 (WT «> 1.33
TVA SOLIDS CHARACTERIZATION
ASH 
-------
                                               TABLE  2.   VENTURI/SPRAY  TOWER SLURRY ANALYSES
                RUN NUMBER
             ANALYSIS POINT
                      DATE
                      TIME
                  ADSORBENT
ON-SITE SOLIDS ANALYSES
 ASH  (NT %)
 CA (WT «)
 S02  (WT *>
 S03  (MT «>
 C02  (NT %)

TVA SOLIDS CHARACTERIZATION
 ASH  (MT %. ACIO INSOLUBLE)
 CAC03 (WT %• BY IR)
 CAS03 X .5 H20 (WT »» IR)
 CAS04 X 2H20 (WT ft* IR)
 SURFACE AREA (SO M/GM)

TVA SLURRY CHARACTERIZATION
 SLURRY SOLIDS %
 SETTLED % SOLIDS
 SETTLED BULK DENSITY (GM/CO
 SETTLING RATE (CM/HR)

TVA CRYSTALLOGRAPHIC ANALYSES
 SULFITE REFRACTIVE INDEX
 SULFITE A AXIS
    STD. ERROR
 SULFITE B AXIS
    STO. ERROR
 SULFITE C AXIS
    STO. ERROR

SCRUBBER OPERATIONAL PARAMETERS
 % SOLID OXIDATION
 SAT. RATIO (RADIAN 50 C.)
 STOIC. RATIO
 SLURRY PH
 SLURRY TEMPERATURE  (C)
 MAKE/PASS  (MOLES/THOUS GAL)
 LIQ/GAS  (6AL/THOUS CFM)
 WT % CL  IN LIQUOR
 WT * MG  IN LIQUOR
 HOLD TANK RES. TIME  
-------
                                  TABLE  2.   VENTURI/SPRAY TOWER SLURRY ANALYSES
    RUN NUMBER   851-1A  851-1A  853-1A  8S3-1A   854-1*  954-1A
ANALYSIS  POINT    1816
1815
1816
1815
1816
1815
          DATE  031577  031577  033377  032377   033977  03Z977
TIME 0715
ADSORBENT LIME
ON-SITE SOLIDS ANALYSES
ASH (WT *) 0.0
CA (MT «) 45.41
S02 (WT %) 35.44
S03 (WT %) 10.11
C02 (WT *) 3.14
TVA SOLIDS CHARACTERIZATION
ASH (WT %. ACID INSOLUBLE) 0.0
CAC03 (WT ft* BY IR) 12.0
CAS03 X .5 H20 
-------
TABLE 3.  SETTLING RATE DETERMINATIONS

Settling rate (cm/h)
Sample ID Muscle Shoals (M)
1816
1816
1816
1816
1816
1816
1816
1816
1816
1816
1816
1816
1816
1816
1816
2816
2816
2816
2816
2816
2816
2816
2816
2816
2816
2816
7/18/75
7/24/75
8/04/75
8/18/75
9/02/75
9/30/75
10/15/75
11/04/75
11/13/75
11/19/75
12/17/75
12/30/75
5/04/76
5/17/76
6/21/76
8/01/75
8/26/75
10/08/75
11/26/75
12/03/75
1/07/76
1/19/76
4/27/76
5/12/76
5/24/76
6/02/76
Total
Mean
Std.

Dev.
37.9
34.2
46.0
5.4
34.5
19.0
4.4
9.6
8.8
9.2
4.1
4.4
5.9
16.4
107.1
5.8
4.5
5.5
9.1
6.2
7.0
6.8
2.7
1.2
3.9
2.0
401.6
15.45
-
Shawnee (S)
52.5
47.5
46.9
5.5
32.0
17.6
4.0
13.1
9.3
11.2
4.1
4.3
6.7
22.0
160.0
5.7
5.5
5.6
10.1
5.4
7.0
7.0
2.7
1.7
4.4
3.5
495.3
19.05
-
S-M = Y
14.6
13.3
0.9
0.1
-2.5
-1.4
-0.4
3.5
0.5
2.0
0.0
-0.1
0.8
5.6
52.9
-0.1
1.0
0,1
1.0
-0.8
0.0
0.2
0.0
0.5
0.5
1.5
93.7
3.60
10.80
Y2
213.2
176.9
0.8
0.0
6.3
2.0
0.2
12.3
0.3
4.0
0.0
0.0
0.6
31.4
2798.4
0.0
1.0
0.0
1.0
0.6
0.0
0.0
0.0
0.3
0.3
2.3
3251.61
-
-
                77

-------
     TABLE 4.   TEMPERATURE OF DEHYDRATION OF CaS03'0.5H20 IN DRIED
               SCRUBBER SOLIDS

Sample
Analysis
3-20-76
4-03-76
4-14-76
4-21-76
5-01-76
5-08-76
5-15-76
5-21-76
5-31-76
6-09-76
6-20-76
6-21-76
6-23-76
6-25-76
6-27-76
7-01-76
7-03-76
7-07-76
7-09-76
7-11-76
7-12-76
7-15-76
7-17-76
Analysis
3-22-76
3-30-76
4-12-76
4-22-76
4-30-76
5-07-76
Temp. °
Point 1816
660
654
664
659
650
656
661
658
658
658
631
650
641
646
646
645
645
655
648
647
649
655
648
Point 2816
658
643
660
658
655
657
Std.
K Dev.a
(Venturi/ spray
4.0
2.3
2.5
7.3
1.2
0.0
1.5
2.3
1.5
0.6
0.6
1.5
1.7
1.4
0.8
1.5
5.9
2.1
1.5
14.2
1.5
1.7
2.6
(TCA)
1.0
3.4
0.6
1.0
3.5
0.6
Sample
tower)
7-20-76
7-22-76
7-24-76
7-26-76
7-30-76
8-01-76
8-07-76
8-09-76
8-11-76
8-17-76
8-20-76
8-22-76
8-25-76
8-26-76
8-27-76
8-28-76
8-29-76
8-30-76
9-05-76
9-10-76
9-16-76
9-23-76
9-28-76

5-14-76
5-22-76
6-01-76
6-10-76
6-19-76

Temp. °K

646
652
647
644
650
640
651
647
651
655
650
646
651
650
652
650
649
649
654
641
633
655
653

658
656
654
657
654

Std.
Dev.a

0.5
0.6
1.0
2.0
0.6
1.0
1.5
0.0
1.5
1.2
2.6
0.6
0.6
0.6
1.5
1.0
2.9
0.6
2.6
4.6
4.9
0.0
19.1

1.0
6.1
1.0
0.6
0.6

JStd.  deviation calculated from 3 observations each sample.
                                78

-------
         TABLE 5.  ANALYTICAL RESULTS FOR GYPSUM DETERMINATION
                   BY DIFFERENTIAL SCANNING CALORIMETRY
               Gypsum, % (wt)
               Known    Found
    Std.  dev.
         Coeff.  var.
10.00
7.00
4.00
1.000
0.600
0.500
0.300
0.100
9.82
6.90
3.94
0.982
0.585
0.490
0.314
0.109
0.30
0.30
0.18
0.046
0.028
0.022
0.015
0.007
3.05
4.34
4.57
4.68
4.79
4.49
4.78
6.42
 TABLE 6.  ANALYTICAL RESULTS FOR THE VENTURI/SPRAY TOWER SLUDGE DATA
     Variable
Mean
Std. Dev.
                                                      Low
                                                     Values
                                                                 High
                                                                Values
A.  Lime Product Sludge (n = 66 data points)
ASH (wt. %)                   31.5
CaO (wt. %)                   29.3
S02 (wt. %)                   24.9
S03 (wt. %)                    7.1
C02 (wt. %)                    1.5
Solids Recirculated (wt. %)   10.4
Oxidation  (wt. %)             19.9
Settled Solids (wt. %)        43.4
Settled Bulk  (g/cc)            1.3
                                         19.11
                                          8.66
                                            14
                                            ,88
                                            18
                                          4.21
                                         18.47
                                          8.12
                                          0.09
            9.
            4.
            1,
                 12
                 21
                 15
                  2
                  1
                  6
                 10
                 35
                  1.2
                                                                   50
                                                                   38
                                                                   34
                                                                   12
                                                                    2.7
                                                                   15
                                                                   90
                                                                   52
                                                                    1.4
B.  Limestone Product Sludge (n = 98 data points)
ASH (wt. %)                   32.5
CaO (wt. %)                   29.7
S02 (wt. %)                   21.1
S03 (wt. %)                    6.0
C02 (wt. %)                    5.5
Solids Recirculated (wt. %)   14.6
Oxidation (wt. %)             21.5
Settled Solids (wt. D        41.3
Settled Bulk  (g/cc)            1.3
                                         16.08
                                          7.86
                                          8.42
                                          3.77
                                          3.36
                                          3.34
                                         21.27
                                          8.56
                                          0.10
                        < 12
                          21
                          15
                           2
                           2
                          11
                          10
                          32
                           1.25
                            50
                            38
                            34
                            12
                             9
                            18
                            90
                            50
                             1.4
                                79

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       TABLE 7.  MEAN VALUES FOR HIGH SETTLED SOLIDS
                             Lime                 Limestone
Variable            High Oxidation  Other   High Oxidation  Other
ASH (wt. %)
CaO (wt. %)
S02 (wt. %)
C02 (wt. %)
Solids Recirculated (wt. %)
Oxidation (wt. %)
Settled Solids (wt. %)
Number of data pts.
55.7
15.6
0.5
0.3
18.6
96.6
65.0
2
33.0
28.9
25.8
6.0
12.9
15.4
55.1
5
64.5
10.3
0.2
0.7
16.4
98.3
63.3
6
38.6
27.4
18.2
6.7
17.7
17.9
53.2
5
         TABLE  8.   MEAN VALUES FOR LOW SETTLED  SOLIDS
      Variable                       Lime           Limestone


 ASH (wt.  %)                         17.0              14.0
 CaO (wt.  %)                         37.5              38.8
 S02 (wt.  %)                         25.2              27.2
 C02 (wt.  %)                          2.8               7.2
 Solids Recirculated (wt.  %)         8.8               9.2
 Oxidation (wt.  %)                  14.8              15.6
 Settled Solids  (wt. %)             26.9              26.9
 Number of data  pts.                 6               11
                             80

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           TABLE 9.   MEAN VALUES FOR HIGH SETTLED BULK DENSITY
                                      Lime
                              Limestone
     Variable
High Oxidation  Other   High Oxidation  Other
ASH (wt. %)
CaO (wt. %)
S02 (wt. %)
C02 (wt. %)
Solids Recirculated
Oxidation (wt. %)
Settled Bulk Density
Number of data pts .




(wt. %)

(g/cc)

55.7
15.6
0.5
0.3
18.6
96.6
1.65
2
34.3
28.8
25.2
3.2
7.6
11.4
1.43
4
64.5
12.0
0.2
0.7
16.4
98.3
1.61
6
32.4
30.5
24.1
4.8
15.2
11.4
1.43
4
          TABLE 10.   MEAN VALUES FOR LOW SETTLED BULK DENSITY
          Variable
                Lime
Limestone
ASH (wt. %)
CaO (wt. %)
S02 (wt. %)
C02 (wt. %)
Solids Recirculated (wt. %)
Oxidation (wt. %)
Settled Bulk Density (g/cc)
Number of data pts.
7.4
42.7
35.5
3.5
7.5
10.8
1.15
4
11.4
40.2
28.2
7.5
7.0
13.0
1.17
8
TABLE 11.  PREDICTED RESPONSE FOR CHANGES IN VARIABLES-LIMESTONE SYSTEM
% Settled
Solids
41.8
38.8
35.6
43.8
62.5
24.3
Settled
Bulk Density
1.37
1.33
1.32
1.38
1.61
1.20
% Sulfite
Solids
15.0
34.0
21.0
21.0
0.4
37.0
% Solids
Recirculated
15.0
15.0
11.0
18.0
18.0
5.0
                                81

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TABLE 12.  COEFFICIENTS AND STANDARD ERRORS FROM REGRESSION ANALYSIS

Dependent Variable
In (% settled solids)
In (% settled solids)
In (settled bulk
density)
In (settled bulk
density)
Sludge
Lime
Limestone
Lime
Limestone
In a
Coef./Std. Error
3.68/0232
2.84/0.133
0.40/0.062
0.14/0.040
bi
Coef./Std. Error
-0.09/0.032
-0.09/0.014
-0.05/0.009
-0.04/0.004
b2
Coef./Std Error
0.15/0.073
0.42/0.044
0.01/0.019
0.09/0.013
Model:  InY = Ina +
                                       b2lnX2
          where Xj = % sulfite solids
                X2 = % solids recirculated
         TABLE 13.   EVALUATION STATISTICS FROM REGRESSION ANALYSIS
Dependent Variable
                               Sludge
                                        F (ni,n2)
s2
  In (% settled solids)

  In (% settled solids)

  In (settled bulk
    density)

  In (settled bulk
    density)
                      Lime     0.26   11.59 (2,63)   0.18   1.20

                   Limestone   0.63   80.51 (2,93)   0.12   1.13


                      Lime     0.47   28.11 (2,63)   0.05   1.05


                   Limestone   0.64   83.34 (2,93)   0.04   1.04
  Multiple Correlation Coefficient'
  2Standard Error of Estimate
                                  82

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                               TECHNICAL REPORT DATA
                         (Please read Instructions on the reverse before completing)
1. REPORT NO.
 EPA-600/7-80-100
                          2.
                                                     3. RECIPIENT'S ACCESSION NO.
4. TITLE ANDSUBTITLE
Processing Sludge: Sludge Characterization Studies
                                 5. REPORT DATE
                                  May 1980
                                                     6. PERFORMING ORGANIZATION CODE
 . AUTHOR(S)
J.L.Crowe (TVA-Chattanooga) andS.K. Scale
 (TVA-Muscle Shoals)
                                                     8. PERFORMING ORGANIZATION REPORT NO.
                                  TVA EDT-109
J. PERFORMING ORGANIZATION NAME AND ADDRESS
Tennessee Valley Authority
Division of Energy Demonstrations and Technology
 hattanooga, Tennessee 47401
                                 1O. PROGRAM ELEMENT NO.
                                  E HE 62 4 A
                                 11. CONTRACT/GRANT NO.
                                  EPA Inter agency Agreement
                                   D5-0721
12. SPONSORING AGENCY NAME AND ADDRESS
 EPA,  Office of Research and Development
 Industrial Environmental Research Laboratory
 Research Triangle Park, NC  27711
                                 13. TYPE OF REPORT AND PERIOD COVERED
                                  Final; 3/75-6/77	
                                 14. SPONSORING AGENCY CODE
                                   EPA/600/13
15. SUPPLEMENTARY NOTES iERL_RTp project officer is Julian W. Jones, Mail Drop 61, 919/
541-2489. lERL-RTP's T.G. Brna is handling details of report completion.
16. ABSTRACT
          The report gives results of slurry and solids characterization studies of
167 samples from the TVA/Shawnee turbulent contact absorber and venturi-spray
tower scrubbing systems. It summarizes the range of variability of solids and corre-
lation of this variability with plant operating conditions. It gives regression models
characterizing settled solids and bulk density as functions of calcium sulfite solids
and solids recirculated. Systems using limestone as absorbent precipitate CaSO3-
0. 5H2O primarily as single plates and relatively flat rosettes; spheroidal aggregates
of many small plate crystals result when lime is used. Sulfite crystal morphology
is independent of scrubber configuration. For limestone systems,  crystal size is
clearly related to stoichiometric ratio (Ca:S); no such relationship is observed for
lime systems. Precipitation and crystal growth rates  are believed responsible for
the difference in sulfite crystal morphology observed between the lime and limestone
systems.  For forced oxidation with either absorbent,  the reaction products have very
large, blocky CaSO4.2H2O crystals; no CaSO3-0. 5H2O forms  are seen.  The peak
area (thermal analysis) resulting from gypsum dehydration is  linearly proportional
to gypsum concentration. A clear distinction between gypsum SO4(-2) and substituted
SO4(-2) in the sample is the basis for the CaSQ4-2H2O determination method used.
 7.
                             KEY WORDS AND DOCUMENT ANALYSIS
                DESCRIPTORS
Pollution
Sludge
Analyzing
Properties
Gas Scrubbing
Calcium
Sulfites
Calcium Carbonates
Calcium Oxides
Gypsum
                                         b. IDENTIFIERS/OPEN ENDED TERMS
                                              c. COSATI Field/Group
Pollution Control
Stationary Sources
Characterization
Calcium Sulfites
13B
07A
14B

13H
07B
08G
18. DISTRIBUTION STATEMENT
 Release to Public
                                          19. SECURITY CLASS (ThisReport)
                                          Unclassified
                                              21. NO. OF PAGES

                                                 91
                      20. SECURITY CLASS (This page)
                      Unclassified
                        22. PRICE
EPA Form 2220-1 (9-73)
                                        83

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